Engine Noise Under Load for GMC Truck GMC Sierra Denali 2006

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

Verify the correct operation of the ignition controls. Refer to Detonation/Spark Knock .

Loose torque converter bolts or improperly installed torque converter - automatic transmission only

1. Inspect the torque converter bolts and flywheel.
2. Verify correct installation of the torque converter.
3. Repair, as required.

Cracked flywheel - automatic transmission

1. Inspect the flywheel bolts and flywheel.
2. Repair, as required.

Excessive connecting rod bearing clearance

1. Inspect the following components:

•	The connecting rod bearings

•	The connecting rods

•	The crankshaft

2. Repair, as required.

Excessive crankshaft bearing clearance

1. Inspect the following components:

•	The crankshaft bearings

•	The crankshaft journals

•	The cylinder block crankshaft bearing bore

2. Repair, as required