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Rusted Camshaft Lobes - Repair Suggestions - keywords cover engine mechanical pitted valvetrain wear

Subject:Rusted Camshaft Lobes - Repair Suggestions

Models:2004-2006 Chevrolet Colorado
2004-2006 GMC Canyon
2006 Hummer H3
with 3.5L Engine (VIN 6 - RPO L52)



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

During internal engine repairs, it may be noticed that some of the camshaft lobes are rusted. This may be due to a camshaft cover concern.

Recommendation/Instructions:

If the above concern is found, replace the following components:

   • 

Any Rusted Camshafts and Camshaft Sprockets

   • 

Camshaft Cover

   • 

Oil Fill Cap

   • 

All Valve Lash Adjusters

   • 

All Valve Rocker Arms

   • 

Engine Oil and Oil Filter

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.