Rear cab mount not tightening up?

[Chilly178]

I bought some cab mounts from GMC Paul's and I got them all in and torqued except for the passenger rear. The bolt ran out of threads and kept turning on the shank, I'm not sure why the other rear didn't do this. I thought I did them both the same. All I did was reuse the metal spacers for the rear and everything else is from the kit. Maybe I put an extra shim on the one side and not the other? Or I need one on the one side?

[toolboxchev]

Something is bent or not lining up properly. Take some measurements and go from there. Your frame may be bent also.

Skill outweighs simple stuff every time. Mind over matter.

[Jcfcamaro]

I'm guessing you either need a shorter bolt or some washers at the bolt head to take some length out. As far as spacers go that's to keep the body lines from cab to box lined up. Or to keep the cab from rocking corner to corner.

[Chilly178]

Well I did notice to that my passenger side cab line sits a bit higher than the box. Then on the other side they are lined up. Maybe because that's the only mount not tightened down?

[Chilly178]

Put the bolts next to each other and the new ones definitely have the threads higher up.

[Chilly178]

Well I think the captured nut that the bolt goes into is stripped. Not sure how it happened but it did. Thinking of putting a locking nut on top of it. Good idea or bad? Is it possible to easily change out the captured nut underneath the gas tank? Any ideas?