In the June issue of Motor Magazine in the Service Slants column, there is a bulletin about GM Trucks 2001-2004 with 6.6L Duramax engines. They state that they want us to be aware that the turbo may fail more than once. In other words it may fail and GM replaces it and it may fail again because the #4 cam bearing may have spun and is blocking the oil supply to the turbo. If this happens the only recourse is to replace the short block or go with a reman engine.

Anybody out there experience this yet?

luckily just once,if you have a turbo failure look down the oil supply hole while you rotate the engine by hand.a spun bearing will be obvious.unfortunately I went thru the turbo replacement before I read the bulletin,a lot of work for nothing.those turbos are no fun to replace.

Wow are you serious??! This is the first I've heard of this. Anyone have more info on this?

Document ID# 1511641
2002 Chevrolet Chevy C Silverado - 2WD Diagnostic Information for Turbo Failure Due to Lack of Oil or Repeat Turbo Failures #03-06-93-001A - (May 18, 2004)

Diagnostic Information for Turbo Failure Due to Lack of Oil or Repeat Turbo Failures 2001-2004 Chevrolet Silverado
2003-2004 Chevrolet Kodiak 4500/5500 Series Models
2001-2004 GMC Sierra
2003-2004 GMC Top Kick 4500/5500 Series Models
with 6.6L Duramax Diesel Engine (VINs 1, 2 - RPOs LB7, LLY)
This bulletin is being revised to add an additional engine code and information. Please discard Corporate Bulletin Number 03-06-93-001 (Section 06-Engine).
If a turbocharger failure is thought to be caused due to lack of oil, the camshaft bearing should be checked. The number 4 camshaft bearing bore feeds the turbocharger oil supply hose. If this camshaft bearing spins in the bore, the turbocharger will be starved for oil. This will cause a failure of the turbocharger. Failure to diagnose this condition will result in repeat turbocharger failures.
Notice: Before installing a new turbocharger, clean any debris or excessive oil from the charge air cooler and intake system to prevent damage to the new turbocharger or an engine overspeed condition.
If the turbocharger has failed, perform the following procedure to verify the condition of the number 4 camshaft bearing before installing a new turbocharger.
<LI type=1>Remove the turbocharger using Service Manual procedures. <LI type=1>Remove the turbocharger oil supply hose. <LI type=1>Visually inspect for correct alignment of the number 4 camshaft bearing oil hole through the turbocharger oil supply hole in the block. If the bearing is not correctly aligned the engine assembly must be replaced. <LI type=1>Turn the engine over by hand 1/2 turn and inspect for camshaft bearing movement, indicating a spun camshaft bearing.
If the camshaft bearing is spun, the engine assembly must be replaced.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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Document ID# 1511641
2002 Chevrolet Chevy C Silverado - 2WD