I believe you have the Monaco RR8R chassis. If so, your motorhome bushings are deteriorating (crumbling away), the originals are a three piece design. You can get a new design bushing from Monaco RV, LLC in Coburg, OR. I believe the phone number is 877-466-6226. The new design bushings are a 1 piece design and much improved. The panhard bar and the trailing arms all take the same bushing, P/N 01803668, Bushing suspension cartridge REV A. They are about $17.00 each, you'll need 10 to do the complete rear suspension. The front suspension is the same as the rear. I have not needed to replace the front suspension bushings on my signature rig as yet.
1998 Monaco Dynasty
Scion Xb
Collin and Alfie the dogs