noisy hubcap

I have a dually and simulator covers. The one on the drivers side rear is the one that is noisy one.The simulator seems to come loose a bit from the wheel and when Its tight against the wheel its ok for bout 4or 5 miles them noisy again. I am new to this site but everyone has been really great and I thank all of you for your information. Rick

Removed the rear covers on our C's duels. No need for them, just in the way. Front cap gets stones in it once in awhile but we are on dirt roads frequently.

I carry a small rubber hammer which works pretty good for making sure the front caps are on tight.

As stated above, switch them and see if the noise moves with it.

OP has a Class C motorhome.

Single, dually, Trailer motor home?
How is attached to wheel?

To many variables for a good answer

swap to other side also ck the tabs if is a pound -on

Is it a Cap or a Simulator? Rear Wheel Simulator would be dished IN. A Cap would be dished OUT, like a Front Wheel.
How is it secured to the wheel? We have the popular VersaLiner Simulators. Six of the "lug nuts" on each one are fake. Two are real and tighten onto the tips of two lugs. I put electrical tape in a crosswise pattern surrounding the two holes that actually tighten. Then I found I had to snug the nuts more than the little tool that comes with the Liners. I use a socket wrench. This quieted a squeaky rear wheel liner. Hard to believe but those big heavy wheels flex as we drive.

Moved from Forum Technical Support

I had a noisy hubcap and it turned out it contained a nut that a squirrel had stored away in it.

posted a pic, of the hub cap. It might help