After traveling I 70 east through Vail I decided to check the bushings again. I 70 in that area has grooves through the asphalt down to the sub base from truck chains during the winter. I had to slow down to 25 in sections to keep my teeth in my head. When I checked, the bushing were beginning to fall apart. Because we are on the road for the summer and couldn't order parts and do it myself, I took it to Freightliner in Colorado Springs. Wasn't too bad, $220 for new bushings washers and nuts. I'll be watching the for the remainder of the summer to see how they are holding up.