Coolant in Engine Oil

Engine Mechanical - 3.0L LM2 Diesel | Diagnostic Information and Procedures | Document ID: 5148371

Cause DEFINITION: Foamy or discolored oil or an engine oil overfill condition may indicate coolant entering the engine crankcase. Low coolant levels, an inoperative cooling fan, or a faulty thermostat may lead to an overtemperature condition which may cause engine component damage. Contaminated engine oil and oil filter should be changed. 1. Inspect the oil for excessive foaming or an overfill condition. Oil diluted by coolant may not properly lubricate the crankshaft bearings and may lead to component damage. Lower Engine Noise, Regardless of Engine Speed 2. Inspect by performing a cylinder compression test. Two cylinders side-by-side on the engine block with low compression may indicate a failed cylinder head gasket. Engine Compression Test	Correction
Faulty external engine oil cooler	Replace the components as required.
Faulty cylinder head gasket	Replace the head gasket and components as required. Cylinder Head Replacement
Warped cylinder head	Replace the cylinder head and gasket. Cylinder Head Replacement
Cracked cylinder head	Replace the cylinder head and gasket. Cylinder Head Replacement
Cracked cylinder liner	Replace the components as required.
Cylinder head or block porosity	Replace the components as required.