
DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTIONS
NOISY VALVES 1. High or low oil level in
crankcase.1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Thin or diluted oil. 2. Change oil and filter.
3. Low oil pressure. 3. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
4. Dirt in lash adjusters. 4. Replace as necessary.
5. Worn rocker arms. 5. Replace as necessary.
6. Worn lash adjusters 6. Replace as necessary.
7. Worn valve guides. 7. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
8. Excessive runout of valve seats
on valve faces.8. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION&
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Connecting rod journal
out-of-round.5. Service or replace crankshaft.
6. Misaligned connecting rods. 6. Replace bent connecting rods.
MAIN BEARING NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check thrust washers for wear.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - LUBRICATION

OIL
STANDARD PROCEDURE - ENGINE OIL SERVICE
The engine oil level indicator (1) is located at the right
rear of the engine on the 3.7L/4.7L engines.
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil, pressure loss or oil foaming can result.
Inspect engine oil level approximately every 800 kilometers (500 miles).Unless the engine has exhibited loss of oil
pressure, run the engine for about five minutes before checking oil level.Checking engine oil level on a cold engine
is not accurate.
To ensure proper lubrication of an engine, the engine oil must be maintained at an acceptable level. The acceptable
levels are indicated between the ADD and SAFE marks on the engine oil dipstick.
1. Position vehicle on level surface.
2. With engine OFF, allow approximately ten minutes for oil to settle to bottom of crankcase, remove engine oil
dipstick.
3. Wipe dipstick clean.
4. Install dipstick and verify it is seated in the tube.
5. Remove dipstick, with handle held above the tip, take oil level reading.
6. Add oil only if level is below the ADD mark on dipstick.
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals described in Maintenance Schedules.
Run engine until achieving normal operating temperature.
1. Position the vehicle on a level surface and turn engine off.
2. Hoist and support vehicle on safety stands.
3. Remove oil fill cap.
4. Place a suitable drain pan under crankcase drain.
5. Remove drain plug from crankcase and allow oil to drain into pan. Inspectdrain plug threads for stretching or
other damage. Replace drain plug if damaged.
6. Install drain plug in crankcase.
7. Lower vehicle and fill crankcase with specified type and amount of engine oil described in this section.
8. Install oil fill cap.
9. Start engine and inspect for leaks.

DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTIONS
NOISY VALVES 1. High or low oil level in
crankcase.1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Thin or diluted oil. 2. Change oil and filter.
3. Low oil pressure. 3. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
4. Dirt in lash adjusters. 4. Replace as necessary.
5. Worn rocker arms. 5. Replace as necessary.
6. Worn lash adjusters 6. Replace as necessary.
7. Worn valve guides. 7. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
8. Excessive runout of valve seats
on valve faces.8. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION&
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Connecting rod journal
out-of-round.5. Service or replace crankshaft.
6. Misaligned connecting rods. 6. Replace bent connecting rods.
MAIN BEARING NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check thrust washers for wear.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
DIAGNOSIS AND TESTING - CYLINDER COMPRESSION PRESSURE
The results of a cylinder compressionpressure test can be utilized to diagnose several engine malfunctions.

OIL
STANDARD PROCEDURE - ENGINE OIL SERVICE
The engine oil level indicator (2) is located at the right
rear of the engine on the 4.7L engines.
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil, pressure loss or oil foaming can result.
Inspect engine oil level approximately every 800 kilometers (500 miles).Unless the engine has exhibited loss of oil
pressure, run the engine for about five minutes before checking oil level.Checking engine oil level on a cold engine
is not accurate.
To ensure proper lubrication of an engine, the engine oil must be maintained at an acceptable level. The acceptable
levels are indicated between the ADD and SAFE marks on the engine oil dipstick.
1. Position vehicle on level surface.
2. With engine OFF, allow approximately ten minutes for oil to settle to bottom of crankcase, remove engine oil
dipstick.
3. Wipe dipstick clean.
4. Install dipstick and verify it is seated in the tube.
5. Remove dipstick, with handle held above the tip, take oil level reading.
6. Add oil only if level is below the ADD mark on dipstick.
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals described in Maintenance Schedules.
Run engine until achieving normal operating temperature.
1. Position the vehicle on a level surface and turn engine off.
2. Hoist and support vehicle on safety stands.
3. Remove oil fill cap.
4. Place a suitable drain pan under crankcase drain.
5. Remove drain plug from crankcase and allow oil to drain into pan. Inspectdrain plug threads for stretching or
other damage. Replace drain plug if damaged.
6. Install drain plug in crankcase.
7. Lower vehicle and fill crankcase with specified type and amount of engine oil described in this section.
8. Install oil fill cap.
9. Start engine and inspect for leaks.

DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTIONS
NOISY VALVES 1. High or low oil level in
crankcase.1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Thin or diluted oil. 2. Change oil and filter.
3. Low oil pressure. 3. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
4. Dirt in lash adjusters. 4. Replace as necessary.
5. Worn rocker arms. 5. Replace as necessary.
6. Worn lash adjusters 6. Replace as necessary.
7. Worn valve guides. 7. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
8. Excessive runout of valve seats
on valve faces.8. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION&
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Connecting rod journal
out-of-round.5. Service or replace crankshaft.
6. Misaligned connecting rods. 6. Replace bent connecting rods.
MAIN BEARING NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check thrust washers for wear.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
DIAGNOSIS AND TESTING - CYLINDER COMPRESSION PRESSURE
The results of a cylinder compressionpressure test can be utilized to diagnose several engine malfunctions.

CONDITION POSSIBLE CAUSES CORRECTION
EXCESSIVE OIL CONSUMPTION
OR SPARK PLUGS OIL FOULED1. CCV System malfunction 1. (Refer to 25 - EMISSIONS
CONTROL/EVAPORATIVE
EMISSIONS - DESCRIPTION) for
correct operation
2. Defective valve stem seal(s) 2. Repair or replace seal(s)
3. Worn or broken piston rings 3. Hone cylinder bores. Install new
rings
4. Scuffed pistons/cylinder walls 4. Hone cylinder bores and replace
pistons as required
5. Carbon in oil control ring groove 5. Remove rings and de-carbon
piston
6. Worn valve guides 6. Inspect/replace valve guides as
necessary
7. Piston rings fitted too tightly in
grooves7. Remove rings and check ring end
gap and side clearance. Replace if
necessary
STANDARD PROCEDURE
STANDARD PROCEDURE - REPAIR DAMAGED OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain the original center line.
Damaged or worn threads can be repaired. Essentially, this repair consistsof:
Drilling out worn or damaged threads.
Tapping the hole with a special Heli-Coil Tap, or equivalent.
Installing an insert into the tapped hole to bring the hole back to its original thread size.
STANDARD PROCEDURE—HYDROSTATIC LOCK
CAUTION: DO NOT use the starter motor to rotate the crankshaft. Severe damage could occur.
When an engine is suspected of hydrostatic lock (regardless of what causedthe problem), follow the steps below.
1. Perform the Fuel Pressure Release Procedure (Refer to 14 - FUEL SYSTEM/FUEL DELIVERY - STANDARD
PROCEDURE).
2. Disconnect the negative cable(s) from the battery.
3. Inspect air cleaner, induction system, and intake manifold to ensure system is dry and clear of foreign material.
4. Place a shop towel around the spark plugs to catch any fluid that may possibly be under pressure in the cylinder
head. Remove the spark plugs.
5. With all spark plugs removed, rotate the crankshaft using a breaker bar and socket.
6. Identify the fluid in the cylinders (coolant, fuel, oil, etc.).
7. Be sure all fluid has been removed from the cylinders.
8. Repair engine or components as necessary to prevent this problem from occurring again.
9. Squirt a small amount of engine oil into the cylinders to lubricate the walls. This will prevent damage on restart.
10. Install new spark plugs. Tighten the spark plugs to 41 Nꞏm (30 ft. lbs.) torque.
11. Drain engine oil. Remove and discard the oil filter.
12. Install the drain plug. Tighten the plug to 34 Nꞏm (25 ft. lbs.) torque.
13. Install a new oil filter.
14. Fill engine crankcase with the specified amount and grade of oil. (Refer to LUBRICATION & MAINTENANCE -
SPECIFICATIONS).

26. Install the fan shroud (3).
27. Install the fan (Refer to 7 - COOLING/ENGINE/
RADIATOR FAN - INSTALLATION).
28. Connect the radiator upper hose.
29. Install the washer bottle.
30. Connect the transmission cooler lines.
31. Install the air cleaner resonator and duct work..
32. Add engine oil to crankcase (Refer to LUBRICA-
TION & MAINTENANCE/FLUID TYPES - SPECI-
FICATIONS).
33. Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
34. Connect battery negative cable.
35. Start engine and inspect for leaks.
36. Road test vehicle.
SPECIFICATIONS
5.7L ENGINE
GENERAL DESCRIPTION
DESCRIPTION SPECIFICATION
Engine Type 90° V-8 OHV
Displacement 5.7 Liters
345 ( Cubic Inches)
Bore 99.5 mm (3.91 in.)
Stroke 90.9 mm (3.58 in.)
Compression Ratio 9.6:1
Firing Order 1-8-4-3-6-5-7-2
Lubrication Pressure Feed - Full Flow
Filtration
Cooling System Liquid Cooled - Forced
Circulation
Cylinder Block Cast Iron
Cylinder Head Aluminum
Crankshaft Nodular Iron
Camshaft Hollow Assembled Camshaft
Pistons Aluminum Alloy
Connecting Rods Powdered Metal
CYLINDER BLOCK

OIL
STANDARD PROCEDURE - ENGINE OIL SERVICE
The engine oil level indicator is located at the left hand of the engine on the 5.7L engines.
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil, pressure loss or oil foaming can result.
Inspect engine oil level approximately every 800 kilometers (500 miles).Unless the engine has exhibited loss of oil
pressure, run the engine for about ten minutes before checking oil level. Checking engine oil level on a cold engine
is not accurate.
To ensure proper lubrication of an engine, the engine oil must be maintained at an acceptable level. The acceptable
levels are indicated between the ADD and SAFE marks on the engine oil dipstick.
1. Position vehicle on level surface.
2. With engine OFF, allow approximately five minutes for oil to settle to bottom of crankcase, remove engine oil
dipstick.
3. Wipe dipstick clean.
4. Install dipstick and verify it is seated in the tube.
5. Remove dipstick, with handle held above the tip, take oil level reading.
6. Add oil only if level is below the ADD mark on dipstick.
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals described in Maintenance Schedules (Refer to LUBRICATION &
MAINTENANCE/MAINTENANCESCHEDULES - DESCRIPTION).
Run engine until achieving normal operating temperature.
1. Position the vehicle on a level surface and turn engine off.
2. Hoist and support vehicle on safety stands.
3. Remove oil fill cap.
4. Place a suitable drain pan under crankcase drain.
5. Remove drain plug from crankcase and allow oil to drain into pan. Inspectdrain plug threads for stretching or
other damage. Replace drain plug if damaged.
6. Install drain plug in crankcase. Torque to 34 Nꞏm ( 25 ft. lbs.).
7. Lower vehicle and fill crankcase with specified type and amount of engine oil described in this section.
8. Install oil fill cap.
9. Start engine and inspect for leaks.
10. Stop engine and inspect oil level.
USED ENGINE OIL DISPOSAL
Care should be exercised when disposing used engine oil after it has been drained from a vehicle engine. Refer to
the WARNING at beginning of this section.