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For 1990-2009 cars only

Parts Information on GMSPO Replacement Connecting Rods - keywords crack cracked crankshaft engine fracture fractured mechanical part rod

Subject:Parts Information on GMSPO Replacement Connecting Rods

Models:2004-2006 Buick Rainier
2004-2006 Chevrolet Colorado
2002-2006 Chevrolet TrailBlazer
2004-2006 GMC Canyon
2002-2006 GMC Envoy
2006 Hummer H3
2002-2004 Oldsmobile Bravada
2005-2006 Saab 9-7x



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

Condition/Concern:

As mentioned in the Engine Component Description Section of SI, the connecting rods and caps of this engine are of a fractured split design to improve durability and reduce internal friction. The fractured connecting rod to connecting rod cap joint has a very precise fit. As a result, it may appear that the rod cap was never separated from the connecting rod during manufacturing of replacement connecting rods. Additionally, the connecting rod cap may stay engaged to the connecting rod when the rod cap bolts are removed until slight pressure is used to disengage the connecting rod cap from the connecting rod.

Recommendation/Instructions:

Both of these issues are a normal characteristic of fractured rod caps due to the precise fit of the connecting rod cap to the connecting rod. If encountered, it may be necessary to remove the rod cap bolts, and lightly tap the base of the connecting rod on a work bench to disengage the rod cap from the connecting rod. As with all connecting rods, proper rod cap orientation is essential during installation.

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.