1. Remove foreign objects from pulley grooves. Replace belt.
RIB OR BELT WEAR
1. Pulley misaligned
2. Installation damage
2. Replace belt
1. Align pulley(s)
BELT SLIPS
LONGITUDAL BELT CRACKING
9GROOVE JUMPING9
(Belt does not maintain correct
position on pulley)
BELT BROKEN (Note: Identify and correct problem before new belt is installed)
2. Abrasive environment
3. Rusted pulley(s) 4. Sharp or jagged pulley groove tips 5. Belt rubber deteriorated
2. Clean pulley(s). Replace belt if necessary 3. Clean rust from pulley(s) 4. Replace pulley. Inspect belt.
5. Replace belt
1. Belt slipping because of insufficient tension
1. Inspect/Replace tensioner if necessary
2. Belt or pulley exposed to substance that has reduced friction (belt dressing, oil, ethylene glycol) 3. Driven component bearing failure (seizure) 4. Belt glazed or hardened from heat and excessive slippage
2. Replace belt and clean pulleys
3. Replace faulty component or bearing 4. Replace belt.
1. Belt has mistracked from pulley groove
1. Replace belt
2. Pulley groove tip has worn away rubber to tensile member
2. Replace belt
1. Incorrect belt tension
2. Pulley(s) not within design tolerance 3. Foreign object(s) in grooves
4. Pulley misalignment 5. Belt cordline is broken
1. Incorrect belt tension
2. Tensile member damaged during belt installation 3. Severe misalignment 4. Bracket, pulley, or bearing failure
1. Inspect/Replace tensioner if necessary
2. Replace pulley(s)
3. Remove foreign objects from grooves 4. Align component 5. Replace belt
1. Replace Inspect/Replace tensioner if necessary 2. Replace belt
3. Align pulley(s) 4. Replace defective component and belt
DR DRIVE BELTS - 3.7L / 4.7L (Continued)
ACCESSORY DRIVE
7 - 27
CONDITION
POSSIBLE CAUSES
CORRECTION
NOISE (Objectionable squeal, squeak, or rumble is heard or felt while drive belt is in operation)
TENSION SHEETING FABRIC FAILURE (Woven fabric on outside, circumference of belt has cracked or separated from body of belt)
CORD EDGE FAILURE (Tensile member exposed at edges of belt or separated from belt body)
1. Incorrect belt tension
2. Bearing noise 3. Belt misalignment 4. Belt to pulley mismatch 5. Driven component induced vibration
1. Tension sheeting contacting stationary object
2. Excessive heat causing woven fabric to age 3. Tension sheeting splice has fractured
1. Incorrect belt tension
2. Belt contacting stationary object 3. Pulley(s) out of tolerance 4. Insufficient adhesion between tensile member and rubber matrix
1. Inspect/Replace tensioner if necessary
2. Locate and repair 3. Align belt/pulley(s) 4. Install correct belt 5. Locate defective driven component and repair
1. Correct rubbing condition
2. Replace belt
3. Replace belt
1. Inspect/Replace tensioner if necessary 2. Replace belt 3. Replace pulley 4. Replace belt
REMOVAL
CAUTION: DO NOT LET TENSIONER ARM SNAP BACK TO THE FREEARM POSITION, SEVER DAM- AGE MAY OCCUR TO THE TENSIONER.
Belt tension is not adjustable. Belt adjustment is maintained by an automatic (spring load) belt ten- sioner.
(1) Disconnect negative battery cable from battery. (2) Rotate belt tensioner until it contacts it’s stop. Remove belt, then slowly rotate the tensioner into the freearm position. (Fig. 8).
INSTALLATION
Belt tension is not adjustable. Belt adjustment is maintained by an automatic ( spring load ) belt ten- sioner.
(1) Check condition of all pulleys.
CAUTION: When installing the serpentine accessory drive belt, the belt MUST be routed correctly. If not, the engine may overheat due to the water pump rotating in the wrong direction (Fig. 8).
(2) Install new belt (Fig. 8). Route the belt around all pulleys except the idler pulley. Rotate the ten- sioner arm until it contacts it’s stop position. Route the belt around the idler and slowly let the tensioner rotate into the belt. Make sure the belt is seated onto all pulleys.
(3) With the drive belt installed, inspect the belt wear indicator (Fig. 9). On 4.7L Engines only, the gap between the tang and the housing stop (measure- ment A) must not exceed 24 mm (.94 inches). If the measurement exceeds this specification replace the serpentine accessory drive belt.
ACCESSORY DRIVE
7 - 28
DRIVE BELTS - 3.7L / 4.7L (Continued)
DR
DRIVE BELTS - 5.9L DIAGNOSIS AND TESTING - ACCESSORY DRIVE BELT
VISUAL DIAGNOSIS
When diagnosing serpentine accessory drive belts, small cracks that run across the ribbed surface of the belt from rib to rib (Fig. 10), are considered normal. These are not a reason to replace the belt. However, cracks running along a rib (not across) are not nor- mal. Any belt with cracks running along a rib must be replaced (Fig. 10). Also replace the belt if it has excessive wear, frayed cords or severe glazing.
Refer to ACCESSORY DRIVE BELT DIAGNOSIS
CHART for further belt diagnosis.
Fig.8BELTROUTING3.7L/4.7L
1 - GENERATOR PULLEY 2 - ACCESSORY DRIVE BELT 3 - POWER STEERING PUMP PULLEY 4 - CRANKSHAFT PULLEY 5 - IDLER PULLEY 6 - TENSIONER 7 - A/C COMPRESSOR PULLEY 8 - WATER PUMP PULLEY
Fig.9AccessoryDriveBeltWearIndicator–4.7L
1 - AUTOMATIC TENSIONER ASSEMBLY
Engine
Fig.10BeltWearPatterns
1 - NORMAL CRACKS BELT OK 2 - NOT NORMAL CRACKS REPLACE BELT
NOISE DIAGNOSIS
Noises generated by the accessory drive belt are most noticeable at idle. Before replacing a belt to resolve a noise condition, inspect all of the accessory drive pulleys for alignment, glazing, or excessive end play.
DR DRIVE BELTS - 5.9L (Continued)
ACCESSORY DRIVE
7 - 29
ACCESSORY DRIVE BELT DIAGNOSIS CHART
CONDITION
POSSIBLE CAUSES
CORRECTION
RIB CHUNKING (One or more ribs has separated from belt body)
1. Foreign objects imbedded in pulley grooves.
1. Remove foreign objects from pulley grooves. Replace belt.
RIB OR BELT WEAR
1. Pulley misaligned
2. Installation damage
2. Replace belt
1. Align pulley(s)
BELT SLIPS
LONGITUDAL BELT CRACKING
9GROOVE JUMPING9
(Belt does not maintain correct
position on pulley)
BELT BROKEN (Note: Identify and correct problem before new belt is installed)
2. Abrasive environment
3. Rusted pulley(s) 4. Sharp or jagged pulley groove tips 5. Belt rubber deteriorated
2. Clean pulley(s). Replace belt if necessary 3. Clean rust from pulley(s) 4. Replace pulley. Inspect belt.
5. Replace belt
1. Belt slipping because of insufficient tension
1. Inspect/Replace tensioner if necessary
2. Belt or pulley exposed to substance that has reduced friction (belt dressing, oil, ethylene glycol) 3. Driven component bearing failure (seizure) 4. Belt glazed or hardened from heat and excessive slippage
2. Replace belt and clean pulleys
3. Replace faulty component or bearing 4. Replace belt.
1. Belt has mistracked from pulley groove
1. Replace belt
2. Pulley groove tip has worn away rubber to tensile member
2. Replace belt
1. Incorrect belt tension
2. Pulley(s) not within design tolerance 3. Foreign object(s) in grooves
4. Pulley misalignment 5. Belt cordline is broken
1. Incorrect belt tension
2. Tensile member damaged during belt installation 3. Severe misalignment 4. Bracket, pulley, or bearing failure
1. Inspect/Replace tensioner if necessary
2. Replace pulley(s)
3. Remove foreign objects from grooves 4. Align component 5. Replace belt
1. Replace Inspect/Replace tensioner if necessary 2. Replace belt
3. Align pulley(s) 4. Replace defective component and belt
ACCESSORY DRIVE
7 - 30
DRIVE BELTS - 5.9L (Continued)
DR
CONDITION
POSSIBLE CAUSES
CORRECTION
NOISE (Objectionable squeal, squeak, or rumble is heard or felt while drive belt is in operation)
TENSION SHEETING FABRIC FAILURE (Woven fabric on outside, circumference of belt has cracked or separated from body of belt)
CORD EDGE FAILURE (Tensile member exposed at edges of belt or separated from belt body)
1. Incorrect belt tension
2. Bearing noise 3. Belt misalignment 4. Belt to pulley mismatch 5. Driven component induced vibration
1. Tension sheeting contacting stationary object
2. Excessive heat causing woven fabric to age 3. Tension sheeting splice has fractured
1. Incorrect belt tension
2. Belt contacting stationary object 3. Pulley(s) out of tolerance 4. Insufficient adhesion between tensile member and rubber matrix
1. Inspect/Replace tensioner if necessary
2. Locate and repair 3. Align belt/pulley(s) 4. Install correct belt 5. Locate defective driven component and repair
1. Correct rubbing condition
2. Replace belt
3. Replace belt
1. Inspect/Replace tensioner if necessary 2. Replace belt 3. Replace pulley 4. Replace belt
REMOVAL
NOTE: The belt routing schematics are published from the latest information available at the time of publication. If anything differs between these sche- matics and the Belt Routing Label, use the sche- matics on Belt Routing Label.This label is located in the engine compartment.
CAUTION: Do not attempt to check belt tension with a belt tension gauge on vehicles equipped with an automatic belt tensioner. Refer to Automatic Belt Tensioner in this group.
Drive belts on these engines are equipped with a spring loaded automatic belt tensioner (Fig. 11). This belt tensioner will be used on all belt configurations, such as with or without power steering or air condi- tioning. For more information, (Refer to 7 - COOL- ING/ACCESSORY DRIVE/BELT TENSIONERS - DESCRIPTION).
(1) Attach a socket/wrench to pulley mounting bolt
of automatic tensioner (Fig. 11).
(2) Rotate tensioner assembly clockwise (as viewed from front) until tension has been relieved from belt.
(3) Remove belt from idler pulley first. (4) Remove belt from vehicle.
Fig.11BeltTensioner-5.9LGasEngines
1 - IDLER PULLEY 2 - TENSIONER 3 - FAN BLADE
DR DRIVE BELTS - 5.9L (Continued) INSTALLATION
CAUTION: When installing the accessory drive belt, the belt must be routed correctly. If not, engine may overheat due to water pump rotating in wrong direction. Refer to (Fig. 12) for correct engine belt routing. The correct belt with correct length must be used.
(Fig. 13)
ACCESSORY DRIVE
7 - 31
(1) Position drive belt over all pulleys except idler pulley. This pulley is located between generator and A/C compressor.
(2) Attach a socket/wrench to pulley mounting bolt
of automatic tensioner (Fig. 11).
(3) Rotate socket/wrench clockwise. Place belt over idler pulley. Let tensioner rotate back into place. Remove wrench. Be sure belt is properly seated on all pulleys.
(4) Check belt indexing marks (Refer to 7 - COOL- ING/ACCESSORY DRIVE/BELT TENSIONERS - DESCRIPTION).
Fig.12BeltRouting-5.9LEngineswithA/C
1 - GENERATOR PULLEY 2 - A/C PULLEY 3 - POWER STEERING PULLEY 4 - CRANKSHAFT PULLEY 5 - WATER PUMP PULLEY 6 - TENSIONER PULLEY 7 - IDLER PULLEY
Fig.13BeltRouting-5.9LEnginesWithoutA/C
1 - GENERATOR PULLEY 2 - IDLER PULLEY 3 - POWER STEERING PULLEY 4 - CRANKSHAFT PULLEY 5 - WATER PUMP PULLEY 6 - TENSIONER PULLEY
DRIVE BELTS - 5.9L DIESEL DIAGNOSIS AND TESTING—ACCESSORY DRIVE BELT
VISUAL DIAGNOSIS
When diagnosing serpentine accessory drive belts, small cracks that run across the ribbed surface of the belt from rib to rib (Fig. 14), are considered normal. These are not a reason to replace the belt. However, cracks running along a rib (not across) are not nor- mal. Any belt with cracks running along a rib must be replaced (Fig. 14). Also replace the belt if it has excessive wear, frayed cords or severe glazing.
ACCESSORY DRIVE
7 - 32
DRIVE BELTS - 5.9L DIESEL (Continued)
Refer to ACCESSORY DRIVE BELT DIAGNOSIS
CHART for further belt diagnosis.
DR
NOISE DIAGNOSIS
Noises generated by the accessory drive belt are most noticeable at idle. Before replacing a belt to resolve a noise condition, inspect all of the accessory drive pulleys for alignment, glazing, or excessive end play.
Fig.14BeltWearPatterns
1 - NORMAL CRACKS BELT OK 2 - NOT NORMAL CRACKS REPLACE BELT
ACCESSORY DRIVE BELT DIAGNOSIS CHART
CONDITION
POSSIBLE CAUSES
CORRECTION
RIB CHUNKING (One or more ribs has separated from belt body)
1. Foreign objects imbedded in pulley grooves.
1. Remove foreign objects from pulley grooves. Replace belt.
RIB OR BELT WEAR
1. Pulley misaligned
2. Installation damage
BELT SLIPS
2. Abrasive environment
3. Rusted pulley(s) 4. Sharp or jagged pulley groove tips 5. Belt rubber deteriorated
1. Belt slipping because of insufficient tension 2. Belt or pulley exposed to substance that has reduced friction (belt dressing, oil, ethylene glycol) 3. Driven component bearing failure (seizure) 4. Belt glazed or hardened from heat and excessive slippage
2. Replace belt
1. Align pulley(s)
2. Clean pulley(s). Replace belt if necessary 3. Clean rust from pulley(s) 4. Replace pulley. Inspect belt.
5. Replace belt
1. Inspect/Replace tensioner if necessary 2. Replace belt and clean pulleys
3. Replace faulty component or bearing 4. Replace belt.
DR DRIVE BELTS - 5.9L DIESEL (Continued)
ACCESSORY DRIVE
7 - 33
CONDITION
POSSIBLE CAUSES
CORRECTION
LONGITUDAL BELT CRACKING
1. Belt has mistracked from pulley groove
1. Replace belt
2. Pulley groove tip has worn away rubber to tensile member
2. Replace belt
9GROOVE JUMPING9
(Belt does not maintain correct
position on pulley)
BELT BROKEN (Note: Identify and correct problem before new belt is installed)
NOISE (Objectional squeal, squeak, or rumble is heard or felt while drive belt is in operation)
TENSION SHEETING FABRIC FAILURE (Woven fabric on outside, circumference of belt has cracked or separated from body of belt)
CORD EDGE FAILURE (Tensile member exposed at edges of belt or separated from belt body)
1. Incorrect belt tension
2. Pulley(s) not within design tolerance 3. Foreign object(s) in grooves
4. Pulley misalignment 5. Belt cordline is broken
1. Incorrect belt tension
2. Tensile member damaged during belt installation 3. Severe misalignment 4. Bracket, pulley, or bearing failure
1. Incorrect belt tension
2. Bearing noise 3. Belt misalignment 4. Belt to pulley mismatch 5. Driven component induced vibration
1. Tension sheeting contacting stationary object
2. Excessive heat causing woven fabric to age 3. Tension sheeting splice has fractured
1. Incorrect belt tension
2. Belt contacting stationary object 3. Pulley(s) out of tolerance 4. Insufficient adhesion between tensile member and rubber matrix
1. Inspect/Replace tensioner if necessary
2. Replace pulley(s)
3. Remove foreign objects from grooves 4. Align component 5. Replace belt
1. Replace Inspect/Replace tensioner if necessary
2. Replace belt
3. Align pulley(s) 4. Replace defective component and belt
1. Inspect/Replace tensioner if necessary
2. Locate and repair 3. Align belt/pulley(s) 4. Install correct belt 5. Locate defective driven component and repair
1. Correct rubbing condition
2. Replace belt
3. Replace belt
1. Inspect/Replace tensioner if necessary 2. Replace belt 3. Replace pulley 4. Replace belt
ACCESSORY DRIVE
7 - 34
DRIVE BELTS - 5.9L DIESEL (Continued)
NOTE: The engine speed sensor face is very close to the accessory drive belt. Inspect engine speed sensor and wire harness for damage when acces- sory drive belt has been replaced due to failure or abnormal conditions.
REMOVAL
CAUTION: Do not attempt to check belt tension with a belt tension gauge on vehicles equipped with an automatic belt tensioner. Refer to Automatic Belt Tensioner in this group.
NOTE: The belt routing schematics are published from the latest information available at the time of publication. If anything differs between these sche- matics and the Belt Routing Label, use the sche- matics on Belt Routing Label.This label is located in the engine compartment.
Drive belts on diesel engines are equipped with a spring loaded automatic belt tensioner. displays the tensioner for vehicles without air conditioning. This belt tensioner will be used on all belt config- urations, such as with or without air conditioning. For more information, (Refer to 7 - COOLING/AC- CESSORY DRIVE/BELT TENSIONERS - DESCRIP- TION).
(1) A 1/2 inch square hole is provided in the auto- matic belt tensioner. Attach a 1/2 inch drive-long handle ratchet to this hole.
(2) Rotate ratchet and tensioner assembly clock- wise (as viewed from front) until tension has been relieved from belt.
(3) Remove belt from water pump pulley first. (4) Remove belt from vehicle.
INSTALLATION
CAUTION: When installing the accessory drive belt, the belt must be routed correctly. If not, engine may
DR
overheat due to water pump rotating in wrong direction. Refer to (Fig. 15) for correct engine belt routing. The correct belt with correct length must be used.
(1) Position drive belt over all pulleys except
water pump pulley.
(2) Attach a 1/2 inch ratchet to tensioner. (3) Rotate ratchet and belt tensioner clockwise. Place belt over water pump pulley. Let tensioner rotate back into place. Remove ratchet. Be sure belt is properly seated on all pulleys.
Fig.15BeltRouting–5.9LDieselEngine
1 - GENERATOR PULLEY 2 - WATER PUMP PULLEY 3 - IDLER PULLEY 4 - POWER STEERING PUMP PULLEY 5 - RADIATOR FAN PULLEY 6 - CRANKSHAFT PULLEY 7 - AUTOMATIC TENSIONER 8 - A/C COMPRESSOR PUMP PULLEY
DR
ENGINE
7 - 35
ENGINE
TABLE OF CONTENTS
page
page
COOLANT
DESCRIPTION
DESCRIPTION - ENGINE COOLANT . . . . . . . 36
DESCRIPTION - HOAT COOLANT . . . . . . . . . 37
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
COOLANT RECOVERY CONTAINER-5.9L
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 38
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 38
COOLANT DEGAS CONTAINER-3.7L/4.7L
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 38
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 39
RADIATOR FAN
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
INSPECTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 40
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 40
RADIATOR FAN - 5.9L DIESEL
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
INSPECTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 41
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 41
ENGINE BLOCK HEATER
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 42
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
DIAGNOSIS AND TESTING — ENGINE BLOCK
HEATER
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 43
ENGINE BLOCK HEATER - 5.9L DIESEL
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 43
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 44
ENGINE COOLANT TEMPERATURE SENSOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 44
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 47
ENGINE COOLANT THERMOSTAT- 5.7L/5.9L
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 47
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
DIAGNOSIS AND TESTING—THERMOSTAT . . . 48
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 49
ENGINE COOLANT THERMOSTAT - 3.7L/4.7L
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 50
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
DIAGNOSIS AND TESTING—THERMOSTAT . . . 51
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 51
ENGINE COOLANT THERMOSTAT - 5.9L
DIESEL
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 52
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
DIAGNOSIS AND TESTING—THERMOSTAT . . . 52
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 53
FAN DRIVE VISCOUS CLUTCH
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 54
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
DIAGNOSIS AND TESTING - VISCOUS FAN
DRIVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
FAN DRIVE VISCOUS CLUTCH - 5.9L DIESEL
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 55
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
DIAGNOSIS AND TESTING - ELECTRONICLY
CONTOLLED VISCOUS FAN DRIVE
. . . . . . . 56
RADIATOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 56
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
DIAGNOSIS AND TESTING—RADIATOR
COOLANT FLOW . . . . . . . . . . . . . . . . . . . . . . 57
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
INSPECTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 58
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 58
RADIATOR - 5.9L DIESEL
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 59
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
DIAGNOSIS AND TESTING—RADIATOR
COOLANT FLOW . . . . . . . . . . . . . . . . . . . . . . 59
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
INSPECTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 60
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 60
RADIATOR PRESSURE CAP
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 60
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING—RADIATOR
CAP-TO-FILLER NECK SEAL . . . . . . . . . . . . . 61
DIAGNOSIS AND TESTING - RADIATOR
CAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
INSPECTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 62
7 - 36
ENGINE
WATER PUMP - 5.9L
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 62
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
DIAGNOSIS AND TESTING—WATER PUMP . . . 62
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
INSPECTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 64
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 64
WATER PUMP - 3.7L/4.7L
DESCRIPTION
DESCRIPTION—WATER PUMP . . . . . . . . . . . 64
DESCRIPTION—WATER PUMP BYPASS . . . . 64
OPERATION
OPERATION—WATER PUMP OPERATION—WATER PUMP BYPASS
. . . . . . . . . . . . 64
. . . . . 65
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
INSPECTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 66
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 66
WATER PUMP - 5.9L DIESEL
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . 67
COOLANT
DESCRIPTION
DESCRIPTION - ENGINE COOLANT
ETHYLENE-GLYCOL MIXTURES
CAUTION: Richer antifreeze mixtures cannot be measured with normal field equipment and can cause problems associated with 100 percent ethyl- ene-glycol.
The use of aluminum cylinder blocks, cylinder heads and water pumps requires special corrosion protection. Only Mopart Antifreeze/Coolant, 5 year/ 100,000Mil;e Formula (ethylene-glycol base coolant with corrosion inhibitors called HOAT, for Hybrid Additive Technology) is recommended. This coolant offers the best engine cooling without corrosion when mixed with 50% distilled water to obtain a freeze point of -37°C (-35°F).
The required ethylene-glycol (antifreeze) and water mixture depends upon the climate and vehicle oper- ating conditions. The antifreeze concentration must always be a minimum of 44 percent, year-round in all climates. If percentage is lower than 44 per- cent, engine parts may be eroded by cavitation, and cooling system components may be severely damaged by corrosion. Maximum protec- tion against freezing is provided with a 68% anti- freeze concentration, which prevents freezing down to
DR
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
DIAGNOSIS AND TESTING—WATER PUMP . . . 67
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
INSPECTION
. . . . . . . . . . . . . . . . . . . . . . . . . . 68
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 68
WATER PUMP INLET TUBE - 5.9L
REMOVAL
REMOVAL - WATER PUMP BYPASS HOSE
WITH AIR CONDITIONING . . . . . . . . . . . . . . . 68
REMOVAL - WATER PUMP BYPASS HOSE
WITHOUT AIR CONDITIONING . . . . . . . . . . . 69
INSTALLATION
INSTALLATION - WATER PUMP BYPASS
HOSE WITH AIR CONDITIONING . . . . . . . . . 70
INSTALLATION - WATER PUMP BYPASS
HOSE WITHOUT AIR CONDITIONING . . . . . . 70
WATER PUMP - 5.7L
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . 71
-67.7° C (-90° F). A higher percentage will freeze at a warmer temperature. Also, a higher percentage of antifreeze can cause the engine to overheat because the specific heat of antifreeze is lower than that of water.
Use of 100 percent ethylene-glycol will cause for- mation of additive deposits in the system, as the cor- rosion inhibitive additives in ethylene-glycol require the presence of water to dissolve. The deposits act as insulation, causing temperatures to rise to as high as 149° C (300° F). This temperature is hot enough to melt plastic and soften solder. The increased temper- ature can result in engine detonation. In addition, 100 percent ethylene-glycol freezes at 22° C (-8° F ).
PROPYLENE-GLYCOL MIXTURES
It’s overall effective temperature range is smaller
than that of ethylene-glycol. The freeze point of 50/50
propylene-glycol and water is -32° C (-26° F). 5° C
higher than ethylene-glycol’s freeze point. The boiling
point (protection against summer boil-over) of propy-
lene-glycol is 125° C (257° F ) at 96.5 kPa (14 psi),
compared to 128° C (263° F) for ethylene-glycol. Use
of propylene-glycol can result in boil-over or freeze-up
on a cooling system designed for ethylene-glycol. Pro-
pylene glycol also has poorer heat transfer character-
istics than ethylene glycol. This can increase cylinder
head temperatures under certain conditions.
Propylene-glycol/ethylene-glycol Mixtures
can cause the destabilization of various corrosion inhibi- tors, causing damage to the various cooling system
DR COOLANT (Continued)
components. Also, once ethylene-glycol and propy- lene-glycol based coolants are mixed in the vehicle, conventional methods of determining freeze point will not be accurate. Both the refractive index and spe- cific gravity differ between ethylene glycol and propy- lene glycol.
DESCRIPTION - HOAT COOLANT
WARNING: ANTIFREEZE IS AN ETHYLENE-GLYCOL BASE COOLANT AND IS HARMFUL IF SWAL- LOWED OR INHALED. IF SWALLOWED, DRINK TWO GLASSES OF WATER AND INDUCE VOMIT- ING. IF INHALED, MOVE TO FRESH AIR AREA. SEEK MEDICAL ATTENTION IMMEDIATELY. DO NOT STORE IN OPEN OR UNMARKED CONTAINERS. WASH SKIN AND CLOTHING THOROUGHLY AFTER COMING IN CONTACT WITH ETHYLENE-GLYCOL. KEEP OUT OF REACH OF CHILDREN. DISPOSE OF GLYCOL BASE COOLANT PROPERLY, CONTACT YOUR DEALER OR GOVERNMENT AGENCY FOR LOCATION OF COLLECTION CENTER IN YOUR AREA. DO NOT OPEN A COOLING SYSTEM WHEN THE ENGINE IS AT OPERATING TEMPERATURE OR HOT UNDER PRESSURE, PERSONAL INJURY CAN RESULT. AVOID RADIATOR COOLING FAN WHEN ENGINE COMPARTMENT RELATED SERVICE IS PERFORMED, PERSONAL INJURY CAN RESULT.
CAUTION: Use of Propylene-Glycol based coolants is not recommended, as they provide less freeze protection and less corrosion protection.
The cooling system is designed around the coolant. The coolant must accept heat from engine metal, in the cylinder head area near the exhaust valves and engine block. Then coolant carries the heat to the radiator where the tube/fin radiator can transfer the heat to the air.
Mopart
Antifreeze/Coolant,
The use of aluminum cylinder blocks, cylinder heads, and water pumps requires special corrosion protection. Year/100,000 Mile Formula (MS-9769), or the equiva- lent ethylene-glycol base coolant with organic corro- sion inhibitors (called HOAT, for Hybrid Organic Additive Technology) is recommended. This coolant offers the best engine cooling without corrosion when mixed with 50% ethylene-glycol and 50% distilled water to obtain a freeze point of -37°C (-35°F). If it loses color or becomes contaminated, drain, flush, and replace with fresh properly mixed coolant solu- tion.
CAUTION: Year/100,000 Mile Formula (MS-9769) may not be mixed with any other type of antifreeze. Mixing of
Antifreeze/Coolant,
MoparT
ENGINE
7 - 37
coolants other than specified (non-HOAT or other HOAT), may result in engine damage that may not be covered under the new vehicle warranty, and decreased corrosion protection.
COOLANT PERFORMANCE
The required ethylene-glycol (antifreeze) and water mixture depends upon climate and vehicle operating conditions. The coolant performance of various mix- tures follows:
Pure Water-Water can absorb more heat than a mixture of water and ethylene-glycol. This is for pur- pose of heat transfer only. Water also freezes at a higher temperature and allows corrosion. 100 percent Ethylene-Glycol-The
corrosion inhibiting additives in ethylene-glycol need the pres- ence of water to dissolve. Without water, additives form deposits in system. These act as insulation causing temperature to rise to as high as 149°C (300°F). This temperature is hot enough to melt plas- tic and soften solder. The increased temperature can result in engine detonation. In addition, 100 percent ethylene-glycol freezes at -22°C (-8°F).
50/50 Ethylene-Glycol and Water-Is the recom- mended mixture, it provides protection against freez- ing to -37°C (-34°F). The antifreeze concentration must always be a minimum of 44 percent, year- round in all climates. If percentage is lower, engine parts may be eroded by cavitation. Maximum protec- tion against freezing is provided with a 68 percent antifreeze concentration, which prevents freezing down to -67.7°C (-90°F). A higher percentage will freeze at a warmer temperature. Also, a higher per- centage of antifreeze can cause the engine to over- heat because specific heat of antifreeze is lower than that of water.
CAUTION: Richer antifreeze mixtures cannot be measured with normal field equipment and can cause problems associated with 100 percent ethyl- ene-glycol.
COOLANT SELECTION AND ADDITIVES
The use of aluminum cylinder blocks, cylinder heads and water pumps requires special corrosion protection. Only Mopart Antifreeze/Coolant, Year/100,000 Mile Formula (glycol base coolant with corrosion inhibitors called HOAT, for Hybrid Organic Additive Technology) is recommended. This coolant offers the best engine cooling without corrosion when mixed with 50% distilled water to obtain to obtain a freeze point of it loses color or becomes contaminated, drain, flush, and replace with fresh properly mixed coolant solution.
-37°C (-35°F). If
ENGINE
7 - 38
COOLANT (Continued)
CAUTION: Do not use coolant additives that are claimed to improve engine cooling.
OPERATION
Coolant flows through the engine block absorbing the heat from the engine, then flows to the radiator where the cooling fins in the radiator transfers the heat from the coolant to the atmosphere. During cold weather the ethylene-glycol or propylene-glycol cool- ant prevents water present in the cooling system from freezing within temperatures indicated by mix- ture ratio of coolant to water.
COOLANT RECOVERY CONTAINER-5.9L DESCRIPTION
The coolant reserve/overflow tank is mounted on top of the fan shroud, and is made of high tempera- ture plastic (Fig. 1).
DR
a convenient and safe method for checking coolant level and adjusting level at atmospheric pressure. This is done without removing the radiator pressure cap. The system also provides some reserve coolant to the radiator to cover minor leaks and evaporation or boiling losses.
As the engine cools, a vacuum is formed in the cooling system of both the radiator and engine. Cool- ant will then be drawn from the coolant tank and returned to a proper level in the radiator.
REMOVAL
(1) Remove recovery hose from radiator. (2) Remove the coolant container to fan shroud
mounting bolt.
(3) Tilt the container backward towards the engine to disengage the mounting pin locking features and lift the container away from the fan shroud (Fig. 1).
INSTALLATION
(1) Align the coolant container mounting pins into the slots on the fan shroud and push the container onto the fan shroud.
(2) Secure the container to the fan shroud with the
bolt. Tighten to 8.5N·m (75 in-lbs).
NOTE: Ensure that mounting pins has engaged.
the locking feature on the
(3) Connect the recovery hose to the radiator (Fig.
1).
COOLANT DEGAS CONTAINER-3.7L/4.7L DESCRIPTION
The coolant degas container is mounted on top of the fan shroud and is made of high temperatyre plas- tic (Fig. 2).
OPERATION
The coolant degas system works in parallel with the radiator. It is fed through a vent line connected to the top of the radiator inlet tank and returns to the engine/coolant pump via the heater return hoses. This plumbing arrangement, together with the inlet thermostat, provides for constant flow through the degas container whenever the engine is running. The air space in the top of the degas container serves sev- eral functions. It provides a volume for the expansion of coolant during engine operation. It provides a space for quick de-aeration of the coolant. Since the container is the highest point in the cooling system, any air trapped in the coolant will quickly be trans- ported to the degas container and be separated out.
Fig.1CoolantRecoveryBottle—5.9L
1 - SCREW 2 - COOLANT RECOVERY CONTAINER 3 - RADIATOR/RADIATOR CAP 4 - FAN SHROUD
OPERATION
The coolant reserve/overflow system works in con- junction with the radiator pressure cap. It utilizes thermal expansion and contraction of coolant to keep coolant free of trapped air. It provides a volume for expansion and contraction of coolant. It also provides
DR COOLANT DEGAS CONTAINER-3.7L/4.7L (Continued)
ENGINE
7 - 39
INSTALLATION
(1) Align the mounting pins into the slots on the fan shroud and push the container into the fan shroud.
(2) Secure the coolant container to the fan shroud
with bolts. Tighten to 8.5 N-m (75 in. lbs).
NOTE: Ensure the locking feature on the mounting pins has engaged.
(3) Connect the supply and return hoses to the container and ensure that the hose clamps are posi- tioned properly.
(4) Refill the cooling system(Refer to 7 - COOLING
- STANDARD PROCEDURE).
RADIATOR FAN REMOVAL
If
the viscous fan drive is replaced CAUTION: because of mechanical damage, the cooling fan blades should also be inspected. Inspect for fatigue cracks, loose blades, or loose rivets that could have resulted from excessive vibration. Replace fan blade assembly if any of these conditions are found. Also inspect water pump bearing and shaft assembly for any related damage due to a viscous fan drive malfunction.
(1) Disconnect negative battery cable from battery. (2) Remove coolant reserve/overflow container from fan shroud and lay aside. Do Not disconnect the hoses or drain coolant from the container.
(3) The thermal viscous fan drive/fan blade assem- bly is attached (threaded) to the water pump hub shaft (Fig. 4). Remove the fan blade/viscous fan drive assembly from the water pump by turning the mounting nut counterclockwise as viewed from the front. Threads on the viscous fan drive are RIGHT- HAND. A 36 MM Fan Wrench should be used to pre- vent pulley from rotating (Fig. 3).
(4) Do Not attempt to remove the fan/viscous fan
drive assembly from the vehicle at this time.
(5) Do Not unbolt the fan blade assembly (Fig. 4)
from viscous fan drive at this time.
(6) Remove the fan shroud-to-radiator mounting
(7) Pull the lower shroud mounts out of the radia-
bolts.
tor tank clips.
(8) Remove the fan shroud and fan blade/viscous fan drive assembly as a complete unit from vehicle. (9) After removing the fan blade/viscous fan drive assembly, do not place the viscous fan drive in a horizontal position. If stored horizontally, silicone
Fig.2CoolantDegasContainer
1 - SCREWS 2 - COOLANT DEGAS CONTAINER 3 - FAN SHROUD 4 - RADIATOR
The air space also acts as sort of a spring that pro- vides constant system pressurization in conjunction with the radiator cap on top of the container. By returning coolant to the pump side of the inlet ther- mostat, the degas container also supplies greater pressure to the coolant pump, providing for enhanced coolant flow at high engine speeds.
The degas container also provides a convenient and safe method for checking the coolant level with out removing the radiator pressure cap. The degas con- tainer does not require a separate overflow container since it was designed with enough volume to provide a coolant reserve and also protect for any after-boil conditions.
REMOVAL
(1) Drain enough coolant from the system so that the degas container is empty. Refer to Draining Cool- ing System 3.7L/4.7L Engines in this group
(2) Loosen the clamps securing the supply and return hoses to the container and remove the hoses. (3) Remove the coolant container to fan shroud
mounting bolts.
(4) Tilt the container back towards the engine to disengage the mounting pin locking features and lift the container away from the fan shroud.
ENGINE
7 - 40
RADIATOR FAN (Continued)
Fig.3UsingSpecialTool6958SpannerWrench
1 - SPECIAL TOOL 6958 SPANNER WRENCH WITH ADAPTER
PINS 8346
2 - FAN
Fig.4FanBlade/ViscousFanDrive-GasEngines-
Typical
1 - WATER PUMP BYPASS HOSE 2 - FAN BLADE ASSEMBLY 3 - VISCOUS FAN DRIVE 4 - WATER PUMP AND PULLEY
fluid in the viscous fan drive could drain into its bearing assembly and contaminate lubricant.
CAUTION: Do not remove water pump pulley-to-wa- ter pump bolts. This pulley is under spring tension.
(10) Remove four bolts securing fan blade assem-
bly to viscous fan drive (Fig. 4).
DR
CAUTION: Some engines equipped with serpentine drive belts have reverse rotating fans and viscous fan drives. They are marked with the word REVERSE to designate their usage. Installation of the wrong fan or viscous fan drive can result in engine overheating.
CLEANING
Clean the fan blades using a mild soap and water.
Do not use an abrasive to clean the blades.
INSPECTION
WARNING: DO NOT ATTEMPT TO BEND OR STRAIGHTEN FAN BLADES IF FAN IS NOT WITHIN SPECIFICATIONS.
If
CAUTION: fan blade assembly is replaced because of mechanical damage, water pump and viscous fan drive should also be inspected. These components could have been damaged due to excessive vibration.
(1) Remove fan blade assembly from viscous fan
drive unit (six bolts).
(2) Lay fan on a flat surface with leading edge fac- ing down. With tip of blade touching flat surface, replace fan if clearance between opposite blade and surface is greater than 2.0 mm (.090 inch). Rocking motion of opposite blades should not exceed 2.0 mm (.090 inch). Test all blades in this manner.
(3) Inspect fan assembly for cracks, bends, or bro-
ken welds. Replace fan if any damage is found.
INSTALLATION
(1) Install fan blade assembly to the viscous fan drive. Tighten the bolts (Fig. 4) to 24 N·m (18 ft. lbs.) torque.
(2) Position the fan shroud and the fan blade/vis- cous fan drive assembly to the vehicle as a complete unit.
(3) Install the fan shroud. (4) Install the fan blade/viscous fan drive assembly
to the water pump shaft (Fig. 4).
(5)
Install the coolant reserve/overflow container
to the fan shroud.
(6) Connect the negative battery cable.
NOTE: Viscous Fan Drive Fluid Pump Out Requirement: After installing a new viscous fan drive, bring the engine speed up to approximately 2000 rpm and hold for approximately two minutes. This will ensure proper fluid distribution within the drive.
DR
ENGINE
7 - 41
RADIATOR FAN - 5.9L DIESEL REMOVAL
CAUTION: If the electronically controlled viscous fan drive is replaced because of mechanical dam- age, the cooling fan blades should also be inspected. Inspect for fatigue cracks, or loose rivets that could have resulted from excessive vibration. Replace fan blade assembly if any of these condi- tions are found. Also inspect wiring harness and connectors for damage.
(1) Disconnect the battery negative cables. (2) Remove the fan shroud lower half. by unsnap-
ping the fastening tabs.
CAUTION: Do not remove the fan pulley bolts. This pulley is under spring tension.
(3) Disconnect electrical connector. (4) The electronically controlled viscous fan drive/ fan blade assembly is attached (threaded) to the fan hub shaft (Fig. 5). Remove the fan blade/fan drive assembly from fan pulley by turning the mounting nut counterclockwise (as viewed from front). Threads on the viscous fan drive are RIGHT-HAND. A Snap-On 36 MM Fan Wrench (number SP346 from Snap-On Cummins Diesel Tool Set number 2017DSP) can be used. Place a bar or screwdriver between the fan pulley bolts to prevent pulley from rotating.
(5) Remove the fan shroud and the fan blade/vis- cous drive as an assembly from vehicle from under the vehicle.
(6) Remove fan blade-to-viscous fan drive mount-
(7) Inspect the fan for cracks, loose or bent fan
ing bolts.
blades.
CAUTION: Some engines equipped with serpentine drive belts have reverse rotating fans and viscous fan drives. Installation of the wrong fan or viscous fan drive can result in engine overheating.
CLEANING
Clean the fan blades using a mild soap and water.
Do not use an abrasive to clean the blades.
INSPECTION
WARNING: DO NOT ATTEMPT TO BEND OR STRAIGHTEN FAN BLADES IF FAN IS NOT WITHIN SPECIFICATIONS.
Fig.5FanBlade/ViscousFanDrive
1 - ELECTRICAL CONNECTOR 2 - VISCOUS FAN DRIVE 3 - FAN BLADE 4 - BOLT 5 - FAN DRIVE
If
CAUTION: fan blade assembly is replaced because of mechanical damage, water pump and viscous fan drive should also be inspected. These components could have been damaged due to excessive vibration.
(1) Remove fan blade assembly from viscous fan
drive unit (six bolts).
(2) Lay fan on a flat surface with leading edge fac- ing down. With tip of blade touching flat surface, replace fan if clearance between opposite blade and surface is greater than 2.0 mm (.090 inch). Rocking motion of opposite blades should not exceed 2.0 mm (.090 inch). Test all blades in this manner.
(3) Inspect fan assembly for cracks, bends, or bro-
ken welds. Replace fan if any damage is found.
INSTALLATION
(1) Install fan blade assembly to electrically con- trolled viscous fan drive. Tighten mounting bolts to 23 N·m (17 ft. lbs.) torque.
(2) Position the fan blade/viscous fan drive to the
vehicle as an assembly.
(3) Install viscous fan drive assembly on fan hub shaft (Fig. 5). Tighten mounting nut to 33 N·m (24 ft. lbs.) torque.
(4) Connect electrical connector.
ENGINE
7 - 42
RADIATOR FAN - 5.9L DIESEL (Continued)
DR
(5) Install the lower fan shroud into position and
verify the locking tabs have seated.
(6) Connect the battery negative cables.
NOTE: Viscous Fan Drive Fluid Pump Out Requirement: After installing a new viscous fan drive, bring the engine speed up to approximately 2000 rpm and hold for approximately two minutes. This will ensure proper fluid distribution within the drive.
ENGINE BLOCK HEATER DESCRIPTION
WARNING: DO NOT OPERATE ENGINE UNLESS BLOCK HEATER CORD HAS BEEN DISCONNECTED FROM POWER SOURCE AND SECURED IN PLACE. THE POWER CORD MUST BE SECURED IN ITS RETAINING CLIPS AND ROUTED AWAY FROM EXHAUST MANIFOLDS AND MOVING PARTS.
An optional engine block heater is available with all models. The heater is equipped with a power cord. The cord is attached to an engine compartment com- ponent with tie-straps. The heater warms the engine providing easier engine starting and faster warm-up in low temperatures. The heater is mounted in a core hole of the engine cylinder block in place of a freeze plug with the heating element immersed in engine coolant. The 5.9L gas powered engine has the block heater located on the right side of engine next to the oil filter (Fig. 6). The 3.7L/4.7L gas powered engines have the block heater located to the rear on the right side of the engine (Fig. 7). OPERATION
The heater warms the engine coolant providing easier engine starting and faster warm-up in low temperatures. Connecting the power cord to a grounded 110-120 volt AC electrical outlet with a grounded three wire extension cord provides the elec- tricity needed to heat the element. DIAGNOSIS AND TESTING — ENGINE BLOCK HEATER
If the unit does not operate, possible causes can be either the power cord or the heater element. Test the power cord for continuity with a 110-volt voltmeter or 110-volt test light. Test heater element continuity with an ohmmeter or a 12-volt test light.
CAUTION: To prevent damage, the power cord must be secured in it’s retainer clips and away from any components that may cause abrasion or damage, such as linkages, exhaust components, etc.
Fig.6EngineBlockHeater-5.9L
1 - FREEZE PLUG HOLE 2 - BLOCK HEATER 3 - SCREW 4 - POWER CORD (120V AC) 5 - HEATING COIL 6 - OIL FILTER
Fig.7EngineBlockHeater-3.7L/4.7L
1 - ENGINE BLOCK HEATER
DR ENGINE BLOCK HEATER (Continued) REMOVAL
(1) Disconnect the battery negative cable. (2) Drain the coolant (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(3) Remove the power cord from the heater by
unplugging (Fig. 8).
(4) Loosen (but do not completely remove) the
screw at center of block heater (Fig. 8).
(5) Remove the block heater by carefully prying from side-to-side. Note the direction of the heating element coil (up or down). The element coil must be installed correctly to prevent damage.
Fig.8EngineBlockHeater
1 - FREEZE PLUG HOLE 2 - BLOCK HEATER 3 - SCREW 4 - POWER CORD (120V AC) 5 - HEATING COIL 6 - OIL FILTER
INSTALLATION
(1) Clean and inspect the block heater hole. (2) Install the new O-ring seal(s) to heater. (3) Insert the block heater into cylinder block and
position the element properly.
(4) With the heater fully seated, tighten center
screw to 2 N·m (17 in. lbs.).
(5) Fill the cooling system with the recommended coolant. (Refer to 7 - COOLING - STANDARD PRO- CEDURE).
(6) Start and warm the engine. (7) Check the block heater for leaks.
ENGINE
7 - 43
ENGINE BLOCK HEATER - 5.9L DIESEL DESCRIPTION
WARNING: DO NOT OPERATE ENGINE UNLESS BLOCK HEATER CORD HAS BEEN DISCONNECTED FROM POWER SOURCE AND SECURED IN PLACE. THE POWER CORD MUST BE SECURED IN ITS RETAINING CLIPS AND ROUTED AWAY FROM EXHAUST MANIFOLDS AND MOVING PARTS.
An optional engine block heater is available on all models. The heater is equipped with a power cord. The heater is mounted in a threaded hole of the engine cylinder block with the heating element immersed in engine coolant. The cord is attached to an engine compartment component with tie-straps.
The 5.9L diesel engine has the block heater located on the right side of the engine below the exhaust manifold next to the oil cooler (Fig. 9).
Fig.9EngineBlockHeater–5.9LDieselEngine
1 - BLOCK HEATER
OPERATION
The heater warms the engine coolant providing easier engine starting and faster warm-up in low temperatures. Connecting the power cord to a grounded 110-120 volt AC electrical outlet with a grounded three wire extension cord provides the elec- tricity needed to heat the element.
REMOVAL
(1) Disconnect the battery negative cables. (2) Drain coolant from radiator and cylinder block (Refer to 7 - COOLING - STANDARD PROCE- DURE).
(3) Unscrew the power cord retaining cap and dis-
connect cord from heater element.
ENGINE
7 - 44
ENGINE BLOCK HEATER - 5.9L DIESEL (Continued)
DR
(4) Using a suitable size socket, loosen and remove
the block heater element (Fig. 10).
Fig.10BlockHeater-DieselEngine
1 - BLOCK HEATER
INSTALLATION
(1) Clean and inspect the threads in the cylinder
block.
ing cap.
(2) Coat heater element
threads with Mopart
Thread Sealer with Teflon.
(3) Screw block heater into cylinder block and
tighten to 43 N·m (32 ft. lbs.).
(4) Connect block heater cord and tighten retain-
(5) Fill cooling system with recommended coolant (Refer to 7 - COOLING - STANDARD PROCE- DURE).
(6) Start and warm the engine. (7) Check block heater for leaks.
ENGINE COOLANT TEMPERATURE SENSOR DESCRIPTION
The Engine Coolant Temperature (ECT) sensor is used to sense engine coolant temperature. The sensor protrudes into an engine water jacket.
The ECT sensor is a two-wire Negative Thermal Coefficient (NTC) sensor. Meaning, as engine coolant temperature increases, resistance (voltage) in the sensor decreases. As temperature decreases, resis- tance (voltage) in the sensor increases.
OPERATION
At key-on, the Powertrain Control Module (PCM) sends out a regulated 5 volt signal to the ECT sensor. The PCM then monitors the signal as it passes through the ECT sensor to the sensor ground (sensor return).
When the engine is cold, the PCM will operate in Open Loop cycle. It will demand slightly richer air- fuel mixtures and higher idle speeds. This is done until normal operating temperatures are reached.
following calculations:
through CCD or PCI (J1850) communications
The PCM uses inputs from the ECT sensor for the † for engine coolant temperature gauge operation † Injector pulse-width † Spark-advance curves † ASD relay shut-down times † Idle Air Control (IAC) motor key-on steps † Pulse-width prime-shot during cranking † O2 sensor closed loop times † Purge solenoid on/off times † EGR solenoid on/off times (if equipped) † Leak Detection Pump operation (if equipped) † Radiator fan relay on/off times (if equipped) † Target idle speed
REMOVAL
3.7L V-6
The Engine Coolant Temperature (ECT) sensor on the 3.7L engine is installed into a water jacket at front of intake manifold near rear of generator (Fig. 11).
WARNING: HOT, PRESSURIZED COOLANT CAN CAUSE INJURY BY SCALDING. COOLING SYSTEM MUST BE PARTIALLY DRAINED BEFORE REMOV- ING THE COOLANT TEMPERATURE SENSOR.
(1) Partially drain the cooling system. (2) Disconnect the electrical connector from the
sensor.
(3) Remove the sensor from the intake manifold.
4.7L V-8
WARNING: HOT, PRESSURIZED COOLANT CAN CAUSE INJURY BY SCALDING. COOLING SYSTEM MUST BE PARTIALLY DRAINED BEFORE REMOV- ING THE ENGINE COOLANT TEMPERATURE (ECT) SENSOR.
The Engine Coolant Temperature (ECT) sensor on the 4.7L V-8 engine is located near the front of the intake manifold (Fig. 12).
(1) Partially drain the cooling system. Refer to 7,
COOLING.
ECT sensor.
(2) Disconnect the electrical connector from the
(3) Remove the sensor from the intake manifold.
DR ENGINE COOLANT TEMPERATURE SENSOR (Continued)
ENGINE
7 - 45
compressor (Fig. 13). It is installed into a water jacket at the front of the cylinder block (Fig. 14).
WARNING: HOT, PRESSURIZED COOLANT CAN CAUSE INJURY BY SCALDING. COOLING SYSTEM MUST BE PARTIALLY DRAINED BEFORE REMOV- ING THE COOLANT TEMPERATURE SENSOR.
(1) Partially drain the cooling system. (2) Remove fan belt. Refer to Accessory Drive in
Cooling section.
(3) Carefully unbolt air conditioning compressor from front of engine. Do not disconnect any A/C hoses from compressor. Temporarily support compressor to gain access to ECT sensor. Refer to Heating and Air Conditioning section for information.
(4) Disconnect electrical
connector
from sensor
(Fig. 14).
(5) Remove sensor from cylinder block.
Fig.11MAPSENSOR/ECTSENSOR-3.7LV-6
1 - MOUNTING SCREWS 2 - MAP SENSOR 3 - ECT SENSOR 4 - FRONT OF INTAKE MANIFOLD
Fig.12ECTSENSOR-4.7LV-8
1 - ECT SENSOR 2 - MOUNTING BOLTS (2) 3 - MAP SENSOR 4 - INTAKE MANIFOLD
5.7L V-8
Fig.13ECTLOCATION-5.7LV-8
1 - TOP OF AIR CONDITIONING COMPRESSOR 2 - ECT SENSOR LOCATION
5.9L Diesel
The Engine Coolant Temperature (ECT) sensor on the 5.9L diesel engine is located near the thermostat housing (Fig. 15).
WARNING: HOT, PRESSURIZED COOLANT CAN CAUSE INJURY BY SCALDING. COOLING SYSTEM MUST BE PARTIALLY DRAINED BEFORE REMOV- ING THE COOLANT TEMPERATURE SENSOR.
The Engine Coolant Temperature (ECT) sensor on the 5.7L engine is located under the air conditioning
(1) Partially drain the cooling system.
ENGINE
7 - 46
ENGINE COOLANT TEMPERATURE SENSOR (Continued)
5.9L V-8 Gas
DR
WARNING: HOT, PRESSURIZED COOLANT CAN CAUSE INJURY BY SCALDING. COOLING SYSTEM MUST BE PARTIALLY DRAINED BEFORE REMOV- ING THE COOLANT TEMPERATURE SENSOR. REFER TO GROUP 7, COOLING.
(1) Partially drain the cooling system. Refer to 7,
(2) Disconnect the electrical connector from the
COOLING.
sensor (Fig. 16).
(3) Engines with air
conditioning: When removing the connector from the sensor, do not pull directly on the wiring harness. The connector is snapped onto the sensor. It is not equipped with a lock type tab.
(4) Remove the sensor from the intake manifold.
Fig.14ECTREMOVE/INSTALL5.7LV-8
1 - FRONT OF INTAKE MANIFOLD 2 - ELECTRICAL CONNECTOR 3 - ECT SENSOR
(2) Disconnect the electrical connector from the
sensor.
(3) Remove the sensor from the cylinder head.
Fig.15ECTLOCATION-5.9LDIESEL
1 - THERMOSTAT HOUSING 2 - ELECTRICAL CONNECTOR 3 - ECT SENSOR
Fig.16ECTSENSOR-5.9LV-8
1 - GENERATOR 2 - A/C COMPRESSOR 3 - ENGINE COOLANT TEMPERATURE SENSOR 4 - ELEC. CONN.
8.0L V-10
The Engine Coolant Temperature (ECT) sensor on the 8.0L V-10 engine is threaded into the thermostat housing (Fig. 17).
WARNING: HOT, PRESSURIZED COOLANT CAN CAUSE INJURY BY SCALDING. COOLING SYSTEM MUST BE PARTIALLY DRAINED BEFORE REMOV- ING THE COOLANT TEMPERATURE SENSOR.
(1) Partially drain the cooling system. (2) Disconnect the electrical connector from the
sensor.
(3) Remove the sensor from the cylinder head.
DR ENGINE COOLANT TEMPERATURE SENSOR (Continued)
ENGINE
7 - 47
(5) Replace any lost engine coolant. Refer to 7,
COOLING.
5.9L Diesel
(1) Apply thread sealant to sensor threads. (2) Install sensor to engine. (3) Tighten sensor to 18 N·m (13 ft. lbs.) torque. (4) Connect electrical connector to sensor. (5) Replace any lost engine coolant. Refer to 7,
COOLING.
5.9L V-8 Gas
(1) Apply thread sealant to sensor threads. (2) Install sensor to engine. (3) Tighten sensor to 6–8 N·m (55–75 in.
lbs.)
torque.
(4) Connect electrical connector to sensor. The sen- sor connector is symmetrical (not indexed). It can be connected to sensor in either direction.
(5) Refill cooling system. Refer to 7, COOLING.
Fig.17ECTSENSOR-8.0LV-10
1 - ENGINE COOLANT TEMP. SENSOR (FOR PCM) 2 - HEATER SUPPLY FITTING 3 - BOLTS (6) 4 - HOUSING WITH INTEGRAL SEAL 5 - THERMOSTAT 6 - RUBBER LIP SEAL 7 - TEMP. GAUGE SENDING UNIT
INSTALLATION
3.7L V-6
(1) Apply thread sealant to sensor threads. (2) Install sensor to engine. (3) Tighten sensor to 11 N·m (8 ft. lbs.) torque. (4) Connect electrical connector to sensor. (5) Replace any lost engine coolant. Refer to 7,
COOLING.
4.7L V-8
(1) Apply thread sealant to sensor threads. (2) Install sensor to engine. (3) Tighten sensor to 11 N·m (8 ft. lbs.) torque. (4) Connect electrical connector to sensor. (5) Replace any lost engine coolant. Refer to 7,
COOLING.
5.7L V-8
(1) Apply thread sealant to sensor threads. (2) Install sensor to engine. (3) Tighten sensor to 11 N·m (8 ft. lbs.) torque. (4) Connect electrical connector to sensor.
8.0L V-10
(1) Apply thread sealant to sensor threads. (2) Install sensor to engine. (3) Tighten sensor to 11 N·m (8 ft. lbs.) torque. (4) Connect electrical connector to sensor. (5) Replace any lost engine coolant. Refer to 7,
COOLING.
ENGINE COOLANT THERMOSTAT- 5.7L/5.9L DESCRIPTION
CAUTION: Do not operate an engine without a ther- mostat, except for servicing or testing.
The thermostat on the 5.7L and 5.9L gas powered engine is located beneath the thermostat housing at the front of the intake manifold (Fig. 18).
The thermostat is a wax pellet driven, reverse pop-
pet choke type.
Coolant leakage into the pellet container will cause the thermostat to fail in the open position. Thermo- stats very rarely stick. Do not attempt to free a ther- mostat with a prying device.
The same thermostat is used for winter and sum- mer seasons. An engine should not be operated with- out a thermostat, except for servicing or testing. Operating without a thermostat causes longer engine warmup time, unreliable warmup performance, increased exhaust emissions and crankcase condensa- tion that can result in sludge formation.
ENGINE
7 - 48
ENGINE COOLANT THERMOSTAT- 5.7L/5.9L (Continued)
DR
REMOVAL
WARNING: DO NOT LOOSEN THE RADIATOR DRAINCOCK WITH THE COOLING SYSTEM HOT AND PRESSURIZED. SERIOUS BURNS FROM THE COOLANT CAN OCCUR.
Do not waste reusable coolant. If the solution is clean, drain the coolant into a clean container for reuse.
If the thermostat is being replaced, be sure that the replacement is the specified thermostat for the vehicle model and engine type.
Factory installed thermostat housings on 5.9L engine is installed on a gasket with an anti-stick coating. This will aid in gasket removal and clean-up.
(1) Disconnect the negative battery cable. (2) Drain the cooling system until the coolant level is below the thermostat (Refer to 7 - COOLING - STANDARD PROCEDURE).
(3) Air Conditioned vehicles: Remove the support bracket (generator mounting bracket-to-intake mani- fold) located near the rear of the generator (Fig. 19).
Fig.19GeneratorSupportBracket–5.9LEngine 1 - IDLER PULLEY BUSHING 2 - A/C AND/OR GENERATOR MOUNTING BRACKET 3 - IDLER PULLEY 4 - SCREW AND WASHER
NOTE: On air conditioning equipped vehicles, the generator must be partially removed.
(4) Remove the accessory drive belt (Refer to 7 - COOLING/ACCESSORY DRIVE/DRIVE BELTS - REMOVAL) (Fig. 20).
(5) Remove the generator mounting bolts. Do not remove any of If equipped with 4WD, unplug the 4WD indicator lamp wiring harness (located near rear of generator).
the wiring at
the generator.
(6) Remove the generator. Position the generator
to gain access for the thermostat gasket removal.
Fig.18Thermostat-5.7L/5.9LGasPowered
Engines
1 - THERMOSTAT HOUSING 2 - GASKET 3 - INTAKE MANIFOLD 4 - THERMOSTAT 5 - MACHINED GROOVE
OPERATION
The wax pellet is located in a sealed container at the spring end of the thermostat. When heated, the pellet expands, overcoming closing spring tension and water pump pressure to force the valve to open.
DIAGNOSIS AND TESTING—THERMOSTAT
ON-BOARD DIAGNOSTICS
All gasoline powered models are equipped with On-Board Diagnostics for certain cooling system com- ponents. Refer to On-Board Diagnostics (OBD) in the Diagnosis section of this group for additional infor- mation. If the powertrain control module (PCM) detects low engine coolant temperature, it will record a Diagnostic Trouble Code (DTC) in the PCM mem- ory. Do not change a thermostat for lack of heat as indicated by the instrument panel gauge or by poor heater performance unless a DTC is present. Refer to the Diagnosis section of this group for other probable causes.
The DTC can also be accessed through the DRBIIIt scan tool. Refer to the appropriate Power- train Diagnostic Procedures information for diagnos- tic information and operation of the DRBIIIt scan tool.
DR ENGINE COOLANT THERMOSTAT- 5.7L/5.9L (Continued)
ENGINE
7 - 49
Fig.20AutomaticBeltTensioner–5.9LEngines
1 - IDLER PULLEY 2 - TENSIONER 3 - FAN BLADE
WARNING: CONSTANT TENSION HOSE CLAMPS ARE USED ON MOST COOLING SYSTEM HOSES. WHEN REMOVING OR INSTALLING, USE ONLY TOOLS DESIGNED FOR SERVICING THIS TYPE OF CLAMP. ALWAYS WEAR SAFETY GLASSES WHEN SERVICING CONSTANT TENSION CLAMPS.
CAUTION: A number or letter is stamped into the tongue of the constant tension clamps (Fig. 21). If is necessary, use only an original replacement equipment clamp with a matching number, letter and width.
(7) Remove the radiator upper hose clamp and
upper hose at the thermostat housing.
(8) Position the wiring harness (behind thermostat
housing) to gain access to the thermostat housing.
(9) Remove
thermostat housing mounting bolts, thermostat housing, gasket and thermostat (Fig. 22). Discard old gasket.
the
INSTALLATION