bolts keep coming loose.

I am looking for the correct size on the bolt that tightens the tranny mount to the tranny. Does anyone know the size of this bolt? Does anyone know how to make it so that this bolt does not com out again? I have tried threadlock... Thanks

I did away with the stock trany mounts and installed chevy 1/2 ton mounts. of course this does take a few modifications to make fit. That fixed the problem for me. I also had a problem with my mounts braking.
I think the bolts are 10mm and about 2 1/2 in. long. Have you tried something as simple as a lock washer? Might work.