Grade 9 bolts

[Rut]

Has anyone ever used grade 9 bolts from Fastenal? I understand that they are just a little stronger than grade 8 and can be used when the are spec.
Thanks, Rut
https://www.fastenal.com/content/feds/pdf/2017/02/High Strength Bolts rev 2017-02-21.pdf https://www.fastenal.com/content/feds/pdf/2017/02/High Strength Bolts rev 2017-02-21.pdf

 

[HealeyRick]

I use Grade 11 fasteners manufactured by Spinal Tap.

 

[BlueMax]

I can assure you will rip the bottom out of the car before a grade 9 180,000 lb sheer bolt gives way...

 

[Rut]

Thanks for the replies and the reason for this post is twofold: 1, the specs on grade 9 and ARP fasteners are similar and the reduced amount of stretch at the same torque is appealing to me. The downsides when used in applications where grade 5 and 8 were used are few as far as these cars are concerned, imho. 2, Fastenal has them on sale in fine thread and I’ve been buying 1/4 thru 3/8 in a variety of lengths for $4-$6 a box. In a critical application I use what’s susposed to be used, but where grade 2 imported stuff is your only choice at the big box stores I like the grade 9...stronger and cheaper.
Thanks, Rut

 

[nomad]

I've always heard that the higher grade fasteners should be only used where vibration and fatigue would not be a problem. That grade 5 was more than adequate for almost everything and less likely to brittle failure. Agree that grade 2 should be avoided for anything other than fencing or building construction.

Kurt

 

[JPSmit]

I just think they are obviously just that one year smarter - High School even!

There were certainly a lot of Grade 9 nuts in my high school!

 

[nomad]

:lol:

Kurt