Safe to drop rearend and re-use hardware?

[Blind]

I'd like to drop my rearend to swap my catback so I don't have to cut the stock one incase I want to switch back to using it.

Would it be safe to undo the u-bolts to drop the rear and then put it all back together when done, or should they be replaced if loosened?

 

[badazzbulldog]

as long as they are in good shape there is no issue

 

[great white]

As a general rule I don't reuse u bolts.

But I usually just cut them off for the trouble they're worth vs the replacement cost.

While they're not torque to yield components, they are subject to a fair amount of stress once torqued and I have seen some that have necked down in the threads with the specified torque applied (which would actually make it seem like they are torque to yield, although I've never seen one listed as such).

Plus, they're inexpensive so why not replace....

That said, if you do reuse them, make sure you verify the torque on them after getting some mileage on them.

Say, a week or 50 miles-ish.

If they need tightening, check them again shortly after. If they need tightening a third time you're best to rip them off and chuck them in the trash as the metal in the bolt has obviously gone past it's yield point and you are at high risk of one breaking on you at a very inopportune moment...

Here's the first thing that showed up on Google for your reading pleasure:

http://www.pirate4x4.com/forum/general-4x4-discussion/863109-reused-u-bolt-failures-2.html

It's pirate4x4 so make sure you have your curse and rude filters up before reading.....

more reading (non cursing):

http://www.eatonsprings.com/ubolttorques.htm

http://www.truckcomponentsonline.com/U-Bolt-Torque-Specifications_df_53.html

Supporting evidence for threads not re-usable: http://www.eng-tips.com/viewthread.cfm?qid=256363

 

[benz88]

You NEVER should reuse Ubolts. The nuts have a special type thread that cuts into the bolt to hold them in place stronger. Once you loosen them and take them off they'll never hold tight again.

 

[Steve's Chevy]

I'm going to change out the rear blocks in mine and yes I'm going to reuse my Ubolts.

 

[96k1500]

I never reuse them but then again ive never gotten a set off without messing them up, they always either bend/twist, or break

 

[Gatorboy]

Don't reuse them, the safety hazard is not worth the money saved initially.

 

[Steve's Chevy]

There are just as many threads saying you can't re'use the Ubolts as there are saying that you can. You be the judge, mine are fairly new ( less than a year old) never over torqued or abused and yes I WILL reuse them for swapping my blocks!

Ubolts are not expensive so.... It's your call!



This message sent straight to you from my Coors light!!

 

[benz88]

Hope it works out. In my opinion I'd rather spend the $30 on new ones instead of risking thousands when that rear end flys off lol.

 

[Gatorboy]

Hope it works out. In my opinion I'd rather spend the $30 on new ones instead of risking thousands when that rear end flys off lol.

That's always been my take on it lol