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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 Or PY9)



This PI was superseded to update model years. Please discard PIT4363.


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 caps they may not properly retain on the threaded lug nut or come loose after driving. This concern has been more noticed in mainly the humid coastal states.

Recommendation/Instructions:

Engineering has found that the lug 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 lug cap, but currently not available. In the meantime, a substitute lug cap that is less sensitive to absorbing moisture is available. Replace all the lug caps with part number 9597158.

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.