71 C10 rear shock bolts breaking

[71C10Guy]

I've had a constant problem with my truck, both rear shocks will eventually wear through the bolts and fall off. I'm not sure why at this point, but I do have 3/4 ton coil springs in her. I thought it might be a missing tracking arm but I realised I do have mine.
Additionally when I first got the truck both lower shock mounts on the rear were completely worn through. I got new mounts from lmctruck and they seem pretty solid, but again both shocks will fall off after either shearing the bolts or just wearing them down.
The truck is stock height as far as I know and I haven't done anything else to the truck suspension. When bolting the shocks on I put a washer on the bolt, the bolt through the shock and mount, then a washer and bolt on the end.
Is this something that just happens with these trucks or is something wrong? Afaik the truck hasn't been in any serious accidents, though there is a big patch of Bondo on the passenger side right above the rear wheel. Could the trailing arm be slightly bent and shearing the shocks?
This happens about every month or two, it's pretty frequent and starting to get expensive replacing 4 grade 8 bolts and nuts as well as 8 washers every month or two.