mm!! is he right??

[budweiser]

i was talking to someone this morning, and scared me a bit, he kept on saying i should replace the bolts of the body lift because aren't strong enough.
got 8.8, and he say i should put 12 tensile strength, is he right? thanks

[Webbo]

8.8 means they are high tensile, and in my opinion don't worry they will be fine. If anything check tightness for peace of mind.

[Albannach]

There is a school of thought that says to drill everything out and use 12mm 8.8 bolts. Personally, I'd go the 12mm 8.8 route. 12.9s are a bit of an overkill (12 doesn't exist as a bolt grade).

[budweiser]

got 10mm thickness is that ok?
thanks

[Albannach]

got 10mm thickness is that ok?
thanks

That's what most people have. I'd say it was fine.

[budweiser]

ah ok, so im fine, so he was talking rubbish (grade 12, it doesn't exist) cool thanks for that.

[Albannach]

ah ok, so im fine, so he was talking rubbish (grade 12, it doesn't exist) cool thanks for that.

Grade 12 bolts don't exist. The bolt grade would be 12.9, the corresponding nut would be grade 12.

[budweiser]

ah, i see

[Webbo]

I've never heard of grade 12 either. Your 8.8 M10 are absolutley fine. We use Girder clamps with M12 8.8 holding I beams with tons and tons of weight hanging off them at work.

[Albannach]

I think, once it goes beyond 8.8, the bolts are steel alloys and very expensive. There's certainly nothing on a truck that would need a higher grade.

[TonyN]

You will pull the bolt heads and washers through the floorpan before the bolts break.

You can tow 3500kg on a tow bar held on with 8.8 bolts, how strong do you need the them?

Don't overtighten them, stretching them only makes the weaker.

[budweiser]

cool thanks to all (peace of mind)