Broke some studs on my fifth wheel. The nuts were tapered at the contact surface. The hex area of the nut was a tad too large and contacted the recess on the rim so that the taper did not contact the rim even though the nuts were torqued. The nuts that were used when the new rims were installed were chrome and longer that the original. It took a close inspection to see the scarring of the recess to determine that. When the smaller, shorter nuts with the chrome covers were reinstalled, I had no further problems.
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