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Black Plastic Center Lug Caps Not Retaining Properly - keywords loose missing nut stripped suspension tight tire trim wheel

Subject:Black Plastic Center Lug Caps Not Retaining Properly

Models:2007-2008 Chevrolet Silverado
2005-2007 Chevrolet Silverado Classic
2007-2008 GMC Sierra
2005-2007 GMC Sierra Classic
With Steel Wheels or Chrome Steel Wheels ( RPO NX7, PY9, PY2)



This PI has been superseded to update Reccomendation/Instruction. Please discard PIT4363A.


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

Condition/Concern:

In some cases, when installing the black plastic lug nut caps they may not properly retain on the threaded lug nut or may come loose after driving.

Recommendation/Instructions:

For vehicles with RPO NX7 or PY9: Engineering has found that the plastic lug nut cap material is sensitive to absorbing moisture and can grow in diameter to the point that the threads no longer engage the threaded lug nut. Engineering is working on updated plastic lug nut caps, but are currently not available. In the meantime, a substitute plastic lug nut cap that is less sensitive to absorbing moisture is available. Replace all the plastic lug nut caps with part number 9597158.

For vehicles with RPO PY2: Engineering has found the root cause to be a vendor tooling error. It is not necessary to replace the center cap with the plastic lug nut caps. Just remove the 8 plastic lug nut caps and replace all the plastic lug nut caps with part number 9597158. Note these caps come 5 to a pack.

Note: In either case please follow the plastic lug nut cap installation procedure outlined in bulletin 03-03-10-002B.

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.