Engine Noise on Start-Up, but Only Lasting a Few Seconds

Cause	Correction
Incorrect oil filter without anti-drainback feature	Install the correct oil filter.
Incorrect oil viscosity	Drain the oil. Install the correct viscosity oil.
High valve lifter leak down rate	Replace the lifters, as required.
Worn crankshaft thrust bearing	Check the crankshaft end play. Inspect the thrust bearing and crankshaft. Repair or replace, as required.
Damaged or faulty oil filter bypass valve	Inspect the oil filter bypass valve for proper operation. Repair or replace, as required.