Yikes, this is a pretty common problem on toyotas and you need to replace the bolts that hold the upper control arms to the frame with Grade 8 bolts. If you need allignment shims, figure out what you need and then use grade 8 washers. If you lose alignment shims when prerunning or racing, you WILL break the bolts and lose your upper arm, probably bending shock shafts and other problems. Trust me.. I know.. .and I've seen it happen to plenty of toyotas... even ones that see little dirt.
I don't have a problem putting them on, just keeping them on. It's real sketchy having your braking pull to one side and hearing the clunk as the bolts shift around. I could just picture them snapping under the stress. I'll make sure to get those replaced soon. So you think putting intact washers on as I am replacing the bolts?
Kartek has the shims to go between the cross-shaft and the frame and as far as keeping the bolts tight, you may have to drill out the 12mm nut-sert that is part of the frame and run 1/2" Grade-8 or better nut and bolt with loc-tite. I did the same thing with my yota and haven't had a problem in two years------ now if I could only get my frame to quit breaking right behind the shock towers I would be set. Any suggestions??
Ditto on the 1/2 inch bolts, washers and locktite for alignment.......as far as the frame cracking goes, I understand that hard bottoming is the culpret, twisting the frame. Plating the inside / outside of the framerails from the motor mount back to the cab mount is the answer.