Incorrect oil filter without anti-drainback feature

Install the correct oil filter.

Incorrect oil viscosity

1. Drain the oil.
2. Install the correct viscosity oil.

High valve lifter leak down rate

Replace the lifters as required.

Worn crankshaft thrust bearing

1. Check the crankshaft end play.
2. Inspect the thrust bearing and crankshaft.
3. Repair or replace as required.

Damaged or faulty oil filter by-pass valve

On certain applications, the valve is now internal to the engine oil filter.