bolt size?

Can someone tell me the bolt size for the pass side nut plate in the rear framerail? I think it's 12mm but I'm not sure. And don't I need to know something else to get the exact bolt (threads per inch or whatever?)

Thanks

It is 12mm but I don't recall if it's 12x1.25 or 12x1.75

The second part is the thread pitch, but in metric it's actually the spacing between threads in mm, not the number of threads per inch. So I think it's 12x1.75

Hey, thanks Eagle! I guess I can pick up both and see which one it is. Now for the million dollar question: Should I use grade 8 or another grade (6? 5?). This is for a hitch. I'm gonna use the carriage bolts that came with the hitch for the drivers side, along with a nut plate I picked up. Those bolts don't fit the nut plate already in the pass side; thus the question.

I don't know the numbers, but the bolts are a coarser thread than standard metric, so if there's a choice, get the coarsest thread they have.

Metric fasteners aren't graded as Grade 5, Grade 8, etc. The factory hitch bolts are very hard, I'd say at least the equivalent of Grade 8, but I don't remember what that's called in metric terms. Grade 10.9 maybe?

Basically, you want hardened bolts, not everyday-strength bolts. The factory bolts have flanged heads, which I have not been able to find an aftermarket source for, so you'll also need matching hardened washers.

The factory bolts also come with loc-tite in the threads. I put anti-sieze on top of that, which is easy because the thread locker is dry. If you can, put blue loc-tite in the threads a couple of days ahead and allow it to dry, then use anti-sieze when you assemble. If you can't loc-tite it ahead of time, skip the loc-tite and use anti-sieze.