Chevrolet Silverado / GMC Sierra. Manual - part 9
Worn, damaged or improperly installed valve
rocker arm
Inspect the valve rocker arms.
Repair or replace damaged components
as required.
Worn or damaged valve rotator
Inspect the valve rotators.
Repair or replace damaged components
as required.
Broken valve spring
Inspect the valve springs.
Repair or replace damaged components
as required.
Worn, damaged or stuck valves, carbon on
the valve stem or valve seat
Inspect the valves.
Inspect the valve guides.
Repair or replace damaged components
as required.
Worn or damaged valve guide
Inspect the valve guides.
Inspect the valves.
Repair or replace damaged components
as required.
Worn, damaged or bent valve push rod
Inspect the valve rocker arms.
Inspect the valve push rods.
Inspect the valve lifters.
Repair or replace damaged components
as required.
Worn, damaged or dirty valve lifter
Inspect the valve lifters.
Repair or replace damaged components
as required.
Worn or damaged camshaft lobes
Inspect the engine camshaft lobes.
Repair or replace damaged components
as required.
Worn, damaged, improperly installed or
loose timing chain and sprockets
Inspect the timing chain and sprockets.
Repair or replace damaged components
as required.
Worn, damaged or improperly installed
timing chain tensioner, if equipped
Inspect the timing chain tensioner.
Repair or replace damaged components
2008 Chevrolet Silverado 1500
2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado
LOWER ENGINE NOISE, REGARDLESS OF ENGINE SPEED
as required.
Cause
Correction
Low oil pressure
1. Verify oil pressure. Refer to Oil
Pressure Diagnosis and Testing.
2. Repair or replace damaged components
as required.
Detonation or spark knock
1. Verify the operation of the ignition
controls system. Refer to Diagnostic
System Check - Vehicle .
2. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
accessory drive belt - severe cracking, bumps
or missing segments in the accessory drive
belt
1. Inspect the accessory drive system
components.
2. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
accessory drive system components
1. Inspect the accessory drive system
components.
2. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
crankshaft balancer
1. Inspect the crankshaft balancer.
2. Inspect the crankshaft.
3. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
engine flywheel
1. Inspect the engine flywheel.
2. Inspect the engine flywheel bolts.
3. Inspect the torque converter.
4. Inspect the torque converter bolts.
5. Inspect the crankshaft.
6. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
torque converter
1. Inspect the torque converter.
2008 Chevrolet Silverado 1500
2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado
2. Inspect the torque converter bolts.
3. Inspect the engine flywheel.
4. Repair or replace damaged components
as required.
Damaged oil pan, contacting the oil pump
screen-An oil pan that has been damaged may
loosen, improperly position, or restrict oil
flow at the oil pump screen, preventing
proper oil flow to the oil pump
1. Inspect the oil pan.
2. Inspect the oil pump screen.
3. Repair or replace damaged components
as required.
Worn, damaged, improperly installed or
restricted oil pump screen-An oil pan that has
been damaged may loosen, improperly
position, or restrict oil flow at the oil pump
screen, preventing proper oil flow to the oil
pump
1. Inspect the oil pan.
2. Inspect the oil pump screen.
3. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
piston-Pistons must be installed with the
mark, or dimple, on the top of the piston,
facing the front of the engine
Piston pins must be centered in the
connecting rod pin bore.
1. Inspect the spark plugs. Refer to Spark
Plug Inspection .
2. Verify engine compression. Refer to
Engine Compression Test.
3. Inspect the cylinder bores.
4. Inspect the pistons.
5. Inspect the piston pins.
6. Inspect the connecting rods.
7. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
connecting rod bearing
1. Inspect the connecting rods.
2. Inspect the connecting rod bearings.
3. Inspect the crankshaft connecting rod
journals.
4. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
crankshaft bearing
1. Inspect the crankshaft bearings.
2. Inspect the crankshaft journals.
3. Repair or replace damaged components
as required.
2008 Chevrolet Silverado 1500
2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado
ENGINE NOISE UNDER LOAD
Cause
Correction
Low oil pressure
1. Perform an oil pressure test. Refer to
Oil Pressure Diagnosis and Testing.
2. Repair or replace as required.
Detonation or spark knock
1. Verify the correct operation of the
ignition controls. Refer to Diagnostic
System Check - Vehicle .
2. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
engine flywheel
1. Inspect the engine flywheel.
2. Inspect the engine flywheel bolts.
3. Inspect the torque converter.
4. Inspect the torque converter bolts.
5. Inspect the crankshaft.
6. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
torque converter
1. Inspect the torque converter.
2. Inspect the torque converter bolts.
3. Inspect the engine flywheel.
4. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
pistons-Pistons must be installed with the
mark, or dimple, on the top of the piston,
facing the front of the engine
Piston pins must be centered in the
connecting rod pin bore.
1. Inspect the cylinder bores.
2. Inspect the pistons.
3. Inspect the piston pins.
4. Inspect the connecting rods.
5. Repair or replace damaged components
as required.
Worn, damaged, or improperly installed
connecting rod bearing
1. Inspect the connecting rods.
2. Inspect the connecting rod bearings.
3. Inspect the crankshaft connecting rod
journals.
4. Repair or replace damaged components
2008 Chevrolet Silverado 1500
2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado