Track bar and grade bolt?

A Grade 8's shear strength is still higher than a Grade 5. :)

Jerry

What part of it causes the grade 8's to snap so easy? Too brittle?

Mike

Jerry Bransford wrote:

this is all new to me, since when do grade 8s snap easily?

I know a few folks that used them in engine mounts and they just shear right off. They would then blow them out of the cast with a torch and try again and again until finally they went back to regular no grade or gr. 5 at the most bolts and the problem stopped.

They are/seem too hard and snap under side impact or shear force.

Same for winch and tow hook mounts.

Mike

The shear strength of a fastener is typically about 60% of its ultimate tension strength. A Grade 8 bolt has a 30% higher tensile strength than a similar Grade

1. Do the math. Use Grade 8. Jim

88 Grand Wagoneer

And then real life steps in and all the math goes out the window....

Mike

Jim Boucher wrote:

Mike, maybe you got a "fake" Grade 8 bolt but a Grade 8's shear strength truly is greater than a Grade 5. A Grade 5 will DEFORM before it breaks giving perhaps greater warning than a Grade 8 will but it will still snap/shear before a Grade 8 will even begin to deform... but a Grade 8 will not deform as much as a Grade 5 will before it snaps.

Jerry

-- bob z.

"people with less brain power than you are doing more difficult things everyday"©

You never know what the local hardware stores are selling. I didn't buy the things, just saw the results as we are strapping his engine in to get him home.

I see all the charts....

Mike

Jerry Bransford wrote:

When I got my winch, Warn said not to use grade 8 bolts for mounting it because of the brittleness. The directions said to use grade 5 to prevent snapping them off.

Sean

Exactly WHO at Warn said that? If it's in written format from Warn, I'd LOVE to see a copy. That's the one of the stupidest things I've ever heard. I am not saying Grade 8 bolts are needed, they aren't, but Grade 8 bolts sure as hell aren't going to snap before a Grade 5 will. :rolleyes: And my Warn winch instructions sure don't warn against using Grade 8 bolts.

Jerry

-- Jerry Bransford To email, remove 'me' from my email address N6TAY, PP-ASEL See the Geezer Jeep at

I'll look through my stuff, it was in the instruction book, I thought it was weird especially since I had already purchased grade 8 bolts to mount it...cost me another trip to the store.

Sean