I have a 2013 GMC 2500. When I got the truck 2 yrs ago I turned up the T-bars a little bit and put a 1'' block in the rear with longer u-bolts. They have been fine and tight for 2 yrs, but today I noticed a rattle from the rear end. I found that all four u-bolts were loose and flopping around. I tried to tighten them and couldn't break the nuts. I had to heat them up to tighten them down. They were seized, so it seems the nuts didn't back themselves off. I looked for a broken leafs, but all seem good.
Why would the u-bolts get loose after 2 yrs??? Any thoughts?
Why would the u-bolts get loose after 2 yrs??? Any thoughts?