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
CYLINDER HEAD
OPERATION—CYLINDER HEAD
The cylinder head closes the combustion chamber allowing the pistons to compress the air fuel mixture to the cor-
rect ratio for ignition. The valves located in the cylinder head open and close to either allow clean air into the com-
bustion chamber or to allow the exhaust gases out, depending on the stroke of the engine.
DIAGNOSIS AND TESTING—CYLINDER HEAD GASKET FAILURE
A cylinder head gasket leak can be located between adjacent cylinders or between a cylinder and the adjacent
water jacket.
Possible indications of the cylinder head gasket leaking between adjacent cylinders are:
− Loss of engine power
− Engine misfiring
− Poor fuel economy
Possible indications of the cylinder head gasket leaking between a cylinder and an adjacent water jacket are:
− Engine overheating
− Loss of coolant
− Excessive steam (white smoke) emitting from exhaust
− Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is leaking between adjacentcylinders, follow the procedures in Cyl-
inder Compression Pressure Test in this section. An engine cylinder head gasket leaking between adjacent cylinders
will result in approximately a 50–70% reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE ENGINE IS OPERATING WITH COOLANT PRESSURE CAP
REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure cap. Start the engine andallow it to warm up until thermostat
opens.
If a large combustion/compression pressure leak exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN PLACE, PRESSURE WILL BUILD UP FAST.EXCESSIVE
PRESSURE BUILT UP, BY CONTINUOUS ENGINE OPERATION, MUST BE RELEASED TO A SAFE PRESSURE
POINT. NEVER PERMIT PRESSURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to pressure cap neck. Start the engine and observe the tester’s
pressure gauge. If gauge pulsates with every power stroke of a cylinder a combustion pressure leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also be checked by using Bloc-Chek Kit C-3685-A or equivalent.
Perform test following the procedures supplied with the tool kit.
CONDITION POSSIBLE CAUSES CORRECTION
11. Directed piston cooling nozzles
under piston, bad fit into main
carrier.11. Check directed piston cooling nozzles
position.
12. Loose oil rifle plug with saddle-jet
style nozzles12.Tighten oil rifle plug.
13. Loose directed piston cooling
nozzle.13. Tighten directed piston cooling nozzle.
14. Both J-jet and saddle jet style
cooling nozzle installed.14. Install correct style jet.
LUBRICATING OIL
PRESSURE TOO HIGH1. Pressure switch/gauge not
operating properly.1. Verify pressure switch is functioning
correctly. If not, replace switch/gauge.
ENGINE BREATHER
RESTRICTED2. Engine running too cold. 2. Refer to Coolant Temperature Below
Normal (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING).
3. Oil viscosity too thick. 3. Make sure the correct oil is being used.
(Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
4. Oil pressure relief valve stuck
closed or binding4. Check and replace valve.
LUBRICATING OIL LOSS 1. External leaks. 1. Visually inspect for oil leaks.Repair as
required.
2. Crankcase being overfilled. 2. Verify that the correct dipstick is being
used.
3. Incorrect oil specification or
viscosity.3. (a) Make sure the correct oil is being
used (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
(b) Look for reduced viscosity from dilution
with fuel.
(c) Review/reduce oil change intervals.
4. Oil cooler leak 4. Check and replace the oil cooler.
5. High blow-by forcing oil out the
breather.5. Check the breather tube area for signs of
oil loss. Perform the required repairs.
6. Turbocharger leaking oil to the air
intake.6. Inspect the air ducts for evidence of oil
transfer. Repair as required.
COMPRESSION KNOCKS 1. Air in the fuel system. 1. Identify location of air leak and repair. Do
not bleed high pressure fuel system.
2. Poor quality fuel or water/gasoline
contaminated fuel.2. Verify by operating from a temporary
tank with good fuel. Clean and flush the
fuel tank. Replace fuel/water separator filter.
3. Engine overloaded. 3. Verify the engine load rating is not being
exceeded.
4. Improperly operating injectors. 4. Check and replace misfiring/inoperative
injectors.
EXCESSIVE VIBRATION 1. Loose or broken engine mounts. 1. Replace engine mounts.
2. Damaged fan or improperly
operating accessories.2. Check and replace the vibrating
components.
DESCRIPTION SPECIFICATION
Engine Type In-Line 6 Cyl. Turbo Diesel
Displacement 5.9 Liters
359 ( Cubic Inches)
Bore 102.0 mm (4.02 in.)
Stroke 120.0 mm (4.72 in.)
Compression Ratio 17.2:1
325 H.P
Cylinder Pressure (Minimum) 350 psi.
Horsepower High Output 48 RE A/T and NV 5600 or G
56 M/T325 HP @ 2900 RPM
Torque Rating High Output ( 48RE A/T and NV 5600 or
G56M/T)610 LB-FT @ 1400 RPM
Lubrication System Pressure Feed-Full Flow With Bypass Valve
Firing Order 1-5-3-6-2-4
Cylinder Block Cast Iron
Crankshaft Induction Hardened Forged Steel
Cylinder Head Cast Iron With Valve Seat Inserts
Combustion Chambers High Swirl Bowl
Camshaft Chilled Ductile Iron
Pistons Cast Aluminum
Connnecting Rods Cross Rolled Micro Alloy
PISTONS
DESCRIPTION SPECIFICATION
Metric Standard
Skirt Diameter 101.775 - 101.793 mm 4.007 - 4.008 in.
Ring Groove Clearance
Intermediate (Min) 0.045 mm .0018 in
(Max) 0.095 mm 0.0037 in.
Oil Control ( Min) 0.040 mm .0016 in.
(Max) 0.085 mm .0033 in.
PISTON PINS
DESCRIPTION SPECIFICATION
Metric Standard
Pin Diameter ( Min) 39.990 mm 1.5744 in.
(Max) 40.003 mm 1.5749 in.
Bore Diameter (Min) 40.006 mm 1.5750 in.
(Max) 40.012 1.5753 in.
PISTON RINGS
page page
ENGINE - 8.3L - SERVICE INFORMATION
DESCRIPTION ............................. 2713
DIAGNOSIS AND TESTING
INTRODUCTION . ......................... 2714
ENGINE DIAGNOSIS - PERFORMANCE .... 2715
ENGINE DIAGNOSIS - MECHANICAL ....... 2716
CYLINDER COMPRESSION PRESSURE
TEST.................................... 2718
CYLINDER COMBUSTION PRESSURE
LEAKAGE TEST.......................... 2718
CYLINDER HEAD GASKET FAILURE
DIAGNOSIS.............................. 2719
HYDRAULIC TAPPET NOISE DIAGNOSIS . . . 2720
ENGINE OIL LEAK INSPECTION ........... 2720
STANDARD PROCEDURE
ENGINE CORE AND OIL GALLERY PLUGS . 2722
FORM-IN-PLACE GASKETS AND SEALERS . 2722
ENGINE GASKET SURFACE
PREPARATION........................... 2723
HYDROSTATIC LOCKED ENGINE .......... 2723
REMOVAL - ENGINE ASSEMBLY . . ........... 2724
INSTALLATION - ENGINE ASSEMBLY ........ 2728
SPECIFICATIONS
ENGINE ................................. 2731
TORQUE ................................. 2736
SPECIAL TOOLS
ENGINE ................................. 2738
SYSTEM-AIR INTAKE
DESCRIPTION ............................. 2741
ELEMENT-AIR CLEANER
REMOVAL ................................. 2742
INSTALLATION ............................. 2743
HOUSING-AIR CLEANER
REMOVAL ................................. 2744
INSTALLATION ............................. 2745
MOUNTS-ENGINE
REMOVAL ................................. 2746
INSTALLATION ............................. 2747
MANIFOLD-INTAKE
DIAGNOSIS AND TESTING
INTAKE MANIFOLD LEAKS ................ 2748
REMOVAL ................................. 2748
INSPECTION ............................... 2750
INSTALLATION ............................. 2751
MANIFOLD-EXHAUST
REMOVAL ................................. 2754
INSPECTION ............................... 2755
INSTALLATION ............................. 2755
HEAD(S)-CYLINDER
REMOVAL - CYLINDER HEAD(S) ............. 2757CLEANING
CLEANING AND INSPECTION............. 2758
INSTALLATION - CYLINDER HEAD(S) ........ 2758
COVER(S)-CYLINDER HEAD
REMOVAL ................................. 2760
INSTALLATION ............................. 2761
ARMS-ROCKER
REMOVAL ................................. 2762
INSTALLATION ............................. 2762
SPRINGS/SEALS-VALVE
DIAGNOSIS AND TESTING
VALVE SPRING TESTING ................. 2763
STANDARD PROCEDURE - VALVE SPRING/
SEAL SERVICE IN-CAR ................... 2763
REMOVAL ................................. 2764
INSTALLATION ............................. 2765
INTAKE/EXHAUST - VALVES/SEATS/GUIDES
STANDARD PROCEDURE - VALVE AND
VALVE SEAT - REFACING ................. 2766
INSPECTION............................... 2767
COVER-TIMING CHAIN
REMOVAL ................................. 2769
INSTALLATION ............................. 2771
TIMING CHAIN AND SPROCKETS
REMOVAL ................................. 2774
INSTALLATION ............................. 2775
LUBRICATION
DESCRIPTION ............................. 2777
OPERATION ............................... 2777
DIAGNOSIS AND TESTING
CHECKING ENGINE OIL PRESSURE ....... 2777
ENGINE OIL LEAK ........................ 2777
OIL
STANDARD PROCEDURE
CHECKING ENGINE OIL LEVEL........... 2779
ENGINE OILAND FILTER CHANGE ........ 2779
COOLER & LINES-OIL
DESCRIPTION ............................. 2781
OPERATION ............................... 2781
STANDARD PROCEDURE - OIL COOLER LINE
QUICK CONNECT FITTING DISASSEMBLY/
ASSEMBLY............................... 2781
REMOVAL ................................. 2782
INSTALLATION ............................. 2783
PAN-OIL
REMOVAL ................................. 2784
INSTALLATION ............................. 2785
PUMP-OIL
REMOVAL ................................. 2788
DISASSEMBLY . ............................ 2788
CLEANING ................................. 2789
3. Clean spark plug recesses with compressed air.
4. Remove the spark plugs.
5. Remove the oil fill cap.
6. Remove the air cleaner.
7. Calibrate the tester according to the manufacturer’s instructions. The shop air source for testing should maintain
483 kPa (70 psi) minimum, 1,379 kPa (200 psi) maximum, with 552 kPa (80 psi) recommended.
8. Perform the test procedures on each cylinder according to the tester manufacturer’s instructions. While testing,
listen for pressurized air escaping through the throttle body, tailpipe and oil filler cap opening. Check for bubbles
in the coolant pressure bottle.
All gauge pressure indications should be equal, with no more than 25 percent leakage per cylinder.
FOR EXAMPLE:At 552 kPa (80 psi) input pressure, a minimum of 414 kPa (60 psi) should be maintained in the
cylinder.
CYLINDER HEAD GASKET FAILURE DIAGNOSIS
A cylinder head gasket leak can be located between adjacent cylinders, between a cylinder and the adjacent water
jacket, or an external coolant leak may be present.
Possible indications of the cylinder head gasket leaking between adjacent cylinders are:
Loss of engine power
Engine misfiring
Poor fuel economy
Possible indications of the cylinder head gasket leaking between a cylinder and an adjacent water jacket are:
Engine overheating
Loss of coolant
Excessive steam (white smoke) emitting from exhaust
Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is leaking between adjacentcylinders, follow the procedures in Cyl-
inder Compression Pressure Test in this section. An engine cylinder head gasket leaking between adjacent cylinders
will result in approximately a 50-70% reduction in compression pressure.Cylinders adjacent to each other will both
have low compression.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: Use extreme caution when the engine is operating with coolant pressure cap removed.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure cap. Start the engine andallow it to warm up until thermostat
opens.
If a large combustion/compression pressure leak exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: With cooling system tester in place, pressure will build up fast.Excessive pressure built up, by
continuous engine operation, must be released to a safe pressure point. Never permit pressure to exceed
138 kpa (20 psi).
Install Cooling System Tester 7700 or equivalent to pressure cap neck. Start the engine and observe the tester’s
pressure gauge. If gauge pulsates with every power stroke of a cylinder a combustion pressure leak is evident.
30. Connect oil cooler lines (4) and connect the oil
pressure sensor (1) and oil temperature sensor
(5).
31. Install the power steering line support bracket at
the radiator.
32. Install lower radiator hose.
33. Connect the cooling fan hydraulic lines (Refer to 7
- COOLING/ENGINE/RADIATOR FAN - INSTAL-
LATION).
34. Connect the A/C line to the fan shroud.
35. Install under body shield.
36. Lower vehicle.
37. Fill engine crankcase with the proper oil to the
correct level (Refer to LUBRICATION & MAINTE-
NANCE/FLUID TYPES - SPECIFICATIONS).
38. Evacuate and recharge the air conditioning (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING - STANDARD PROCEDURE).
39. Fill the cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
40. Fill power steering to proper leveland purge the system (Refer to 19 - STEERING/PUMP - STANDARD PRO-
CEDURE).
41. Connect the negative battery cable.
42. Start the engine and run until operating temperature is obtained.
43. Turn engine off and inspect for leaks.
44. Recheck all fluid levels, fill as required.
SPECIFICATIONS
ENGINE
GENERAL SPECIFICATIONS
DESCRIPTION SPECIFICATION
Ty pe 9 0° V-1 0
Number of Cylinders 10
Firing Order 1-10-9-4-3-6-5-8-7-2
Compression Ratio 9.6:1
Brake Horsepower 501@5600 RPM
Torque 525 ft. lbs. @4100 RPM
Crankshaft Forged Steel
Cylinder Block Aluminum Alloy with Interference Fit Cast Iron Liners
Connecting Rods Cracked Cap Powdered Metal
Pistons Cast Aluminum Alloy
Metric Standard
Displacement 8.3L 505 cu. in.
Bore 102.4 mm 4.03 in.
Stroke 100.6 mm 3.96 in.
Compression Pressure 1069-1172 kPa 155-170 psi
Engine Weight (Approx.) 284 Kilograms 625 Lbs.
OPERATION
Exhaust gas pressure and energy drive the turbine,
which in turn drives a centrifugal compressor that
compresses the inlet air, and forces the air into the
engine through the charge air cooler and plumbing.
Since heat is a by-product of this compression, the air
must pass through a charge air cooler to cool the
incoming air and maintain power and efficiency.
Increasing air flow to the engine provides:
Improved engine performance
Lower exhaust smoke density
Improved operating economy
Altitude compensation
Noise reduction.
The turbocharger features a wastegate , which regu-
lates intake manifold air pressure and prevents over
boosting at high engine speeds and loads. When the
wastegate valve is closed, all of the exhaust gases
flow through the turbine wheel. As the boost pressure
(compressor outlet ) increases, the boost pressure is
fed to the wastegate actuator via a wastegate signal
line. When sufficient boost pressure is achieved, the
boost pressure applied to the wastegate diaphragm
overcomes spring pressure and moves an actuator
rod to open an exhaust bypass valve. When exhaust
gas is diverted from the turbine wheel, turbine shaft
speed is limited which reduces compressor wheel
speed, thereby limiting boost pressure.
The turbocharger wastegate system incorporates, an
Electronically Controlled Wastegate Command Valve,
to control boost pressure. The command valve is
located on the turbocharger compressor housing.
When the command valve is not actuated (no current supplied to the valve), apassage in the valve allows the
wastegate signal line to be supplied with boost pressure. This allows boost pressure to be mechanically regulated
by the wastegate as in a conventional wastegated system.
When the engine control module (ECM) provides a pulse width modulated (PWM) signal to the command valve,
boost pressure is bypassed away from the wastegate signal line through a drilling in the turbocharger compressor
housing. The internal drilling bleeds boost pressure back to the turbocharger compressor inlet (low pressure). Actu-
ating the command valve, (bypassing the boost pressure signal to the wastegate) allows the engine to operate at a
higher boost than would be achieved if the wastegate were allowed to operate normally.
Actuating the command valve does not increase boost pressure if the boost pressure is below the wastegate actua-
tor setting. With the command valve actuated, maximum boost pressure at a given operating condition will vary
based on ambient atmospheric pressure and temperature.