GM Service Manual Online
For 1990-2009 cars only

Cause

Correction

Incorrect engine oil, viscosity

Install the correct engine oil and oil filter

Incorrect oil filter, without anti-drainback feature.

Install the correct engine oil and oil filter.

Worn, damaged, or improperly installed oil filter by-pass valve

  1. Inspect the oil filter by-pass valve.
  2. Repair or replace damaged components as required.

High valve lifter leak down rate

  1. Inspect the valve lifters.
  2. Repair or replace damaged components as required.

Worn, damaged, or improperly installed crankshaft thrust bearing

  1. Inspect the crankshaft.
  2. Inspect the crankshaft thrust bearing.
  3. Repair or replace damaged components as required.