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Oil Leak At Turbocharger Air Intake Pipe - keywords 6.6 BQMI CAC charge clamp cooler crankcase diesel engine inlet LMM PCV positive rear seep seepage turbo valley ventilation

Subject:Oil Leak At Turbocharger Air Intake Pipe

Models:2007-2008 Chevrolet Express, Kodiak, Silverado
2007-2008 GMC Savana, Sierra, Topkick
Equipped with the 6.6L diesel engine RPO code LMM



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

Condition/Concern:

A dealer may encounter a customer concern of an engine oil leak. Initial inspection may reveal a leak that looks like it is coming from the rear of the engine. The leak may actually be coming from the turbocharger inlet pipe (Air Intake Pipe). This leak may run rearwards in the intake valley making the leak seem like a rear of engine oil leak.

Recommendation/Instructions:

Complete the current SI diagnostics for any trouble codes or symptoms found. Verify the leak is coming from the turbocharger air inlet pipe. The pipe is connected to the turbo with a band type retaining clamp. See SI illustration below.


Object Number: 1873381  Size: SH

Important: Oil in the charge air cooler, hoses, turbocharger, or intake manifolds is normal with a closed crankcase ventilation system.

If the oil leak has been verified at the turbo inlet pipe complete the diagnosis below.

  1. Check for an overfilled crankcase.
  2. Verify the proper oil is being used per owner's manual specifications.
  3. Inspect and verify the leak is NOT from the turbocharger oil return pipe.
  4. Check for excessive crankcase pressure using current SI diagnostics for "Crankcase Ventilation System Inspection/Diagnosis."

If diagnostics were inconclusive and a dealer has an excessive oil leak at the Turbo Air Intake Pipe please call engineering directly. Contact information below.

 

Nate Hara

Cell phone

810-845-2545

 

If Nate does not answer please leave a short message with a phone number you can be reached at. If you don't hear back from Nate in four hours make repairs as necessary.

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.