Engine Oil or Fluid in Coolant Diagnosis

Engine Mechanical - 5.3L L84 or 6.2L L87 | Diagnostic Information and Procedures | Document ID: 4969446

Cause	Correction
DEFINITION: Foamy or discolored engine coolant or a coolant “overfill” condition may indicate engine oil, transmission fluid or power steering fluid entering the cooling system. This may result in low engine oil, transmission fluid or power steering fluid levels. 1. Inspect the coolant for excessive foaming, presence of oil or an over fill condition. 2. Check the engine oil level. 3. Check the transmission fluid level. {If equipped with a transmission fluid cooler} 4. Check the power steering fluid level. {If equipped with a power steering fluid cooler}
Fluid Coolers
Engine oil, transmission or power steering cooler {If equipped}. Some models may have cooler lines that pass through a radiator or heat exchanger. Plug passages and/or cooler lines. Supply compressed air and check for internal leaks or pressure drop.	Replace the components as required.
Cylinder Heads
Test for compression gases in engine coolant.
Faulty Cylinder Head Gasket	Replace the head gasket and components as required.
Warped Cylinder Head	Machine the cylinder head, if applicable. Engine Mechanical Specifications
Cracked Cylinder Head	Replace the cylinder head.
Cylinder Head or Block Porosity	Replace the components as required.
Cylinder Block
Cracked Liner or Engine Block	Replace the components as required.
Cylinder Block Porosity	Replace the components as required.