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reusing u-bolts with low milage?

muddybuddy

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ive got ubolts that i used for about 1k miles or so and then i took them off. will i be able to reuse them once i do my lift since they have low milage, or should i go get new ones made? not trying to take a shortcut, just curious. i know usually u shouldnt reuse them, but given the milage i was wondering if there was a difference. thanks
 
Ubolts are torque to yeild, so once your torque them to spec, you cannot re-torque them and expect them to stay tight...

Yes, some people will argue that there is no problem with doing what you want, but others will argue right back that they've seen ubolt failure for the same reason.

Pretty much the best answer is: Do you want a safe truck? Spend the money! Maybe you can get by for now, but please dont leave it like that permenantly, and for the love of god: check them regularly!
 
i check them regularly regardless, i was just asking if it was fine to run them since they were low milage. i had heard bout the torque thing, but i thought it was for a long period of time (lots of miles or 1+ years or something)
 
nope, once they are torqued to the 150-ish ft-lb range they are either on forever or in the garbage can. Its a stress enduced failure thing, 5 mins or 5 years... its all the same.

that being said, mine are torqued to 100-ish right now so i can make final adjustments to my suspension, then when im sure ive got it, ill crank them the rest of the way and hit the road
 
150lbs? mine might still be usable then cuz i think i only torqued them to 115lbs.:doah: next time will be 150lbs thats for sure
 
muddybuddy said:
150lbs? mine might still be usable then cuz i think i only torqued them to 115lbs

uhhh... i may be wrong in that number. I just seem to remember 5/8" ubolts = 140 to 150 ft lbs for some reason, I have no source to back that up
 
I always do 150ft-lbs. That was what the directions said for a lift I installed years ago, and I've just continued using the same spec.
 
If you do decide to reuse the U-bolts you should, at the bery least, replace the nuts. The threads in the nuts yield before the threads on the u-bolt. If the washers show any sign of gauling those should be replace as well. Make sure they are the extra thick, through-hardened washers though.

muddybuddy said:
150lbs? mine might still be usable then cuz i think i only torqued them to 115lbs.:doah: next time will be 150lbs thats for sure




_
 
well i dont wana risk losing the axle and end of destroying the truck, ill just use these as a template for the new ubolts. thanks
 
muddybuddy said:
well i dont wana risk losing the axle and end of destroying the truck, ill just use these as a template for the new ubolts. thanks

If you only had them at 115, then i say your fine to use them again at 150, you were at 75% of the required torque, so you're cool to reuse them
 
mechted said:
Ubolts are torque to yeild...

No they aren't. If they were torque to yield, then the spec would be something like "150 ft-lbs plus 90°"

Not saying that no vehicle uses torque-to-yield u-bolts but 73-91 straight-axle Chevys don't.
 
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