The usual argument among the off road groups is that the lower grade (US
grade 5) bolts bend rather than break like the higher grade (US grade 8)
bolts. That's true but the grade 8 bolts take more stress than the grade
5 bolts do before they break. The off roaders like the bolts that bend,
it gives them a visual cue that they are about to do destructive things
to their rigs. But that means that the bolts that hold (and bend) are
the lower level items. And the argument goes on.



Jon Danniken wrote:
Howdy,

I recently purchased some (metric) bolts to attach a receiver hitch to my
Jeep. While the factory doesn't specify the grade, the nuts they go into
have a six (or possibly a 60) on them.

I didn't purchase the bolts from the stealership, because they want $11.00
(eleven dollars) *per* bolt, so I bought them from Fastenal instead.

When I bought the bolts, I got them in a grade 10.9 (metric).

Earlier today, I came across a discussion on a Jeep forum where someone
alluded to their belief that higher grade bolts would be too "brittle" for
this application.

Personally, I think I'm going to be just fine, but I know someone here will
have something more substantial than my gut feeling.

So, do you think I should order some different bolts, or will I likely be
just fine with the ones I already have?.

Thanks,

Jon