jg22

Can these things be on too tight? I've read a lot of varying numbers for the proper torque.

cruiser54

Kinda vague link....

jg22

I've seen as low as 40, some say 100+, some say as tight as possible, some say depends on the ubolts. I'm getting all this info from using the search function.

cruiser54

Leaf spring u bolts?

55 pounds for 1/2" bolts and 100 for 9/16" bolts. from the factory service manual.

srb53150

well consider this, when i went from 1/2 to 9/16 on my 8.25 i thought well 100 ibs is right for 9/16. so i tighten to that. drove around a few days & noticed my drivers side was sitting lower then the pass. side in the rear, measure it & its a 1/4 " difference. it was always dead even before the u bolt change, so i crawl under & start looking. the u bolts had crushed into the housing tube on that side by a 1/4 ". to get it level i had to loosen all 4 u bolts , put a 1/4 " shim on the drivers side perch. then i retightened all 4 to 65 lbs. been fine ever since. i have never seen anything like this before, so looks like you can go too tight at least for the housing tube that is. wierd thing is it only dented in on the one side ?

jg22

Appreciate the responses. The reason I ask is because on my 8.8 swap I torqued to 100 (they are 9/16). The tops of the u bolts that would get cut off are now not completely straight up and down after torqueing the bolts.

Jeep Driver

The BOLT specifies the torque....>>NOT the FSM.

The 9/16 grade 8 bolts that I used called for 75lbs.

Yes, you will crush the tube.

jg22

So I called ECGS today to find out the torque specs. They said torque to 105....

cruiser54

Huh? The FSM differentiated the torques according to U-bolt size......

Jeep Driver

What grade 9/18 ubolt came from the factory?

You want to bet it was a grade 5?

Will a 5 stretch more than a 8?

cruiser54

Who knows?

I've never put a torque wrench on a ubolt in my life and I've (gasp!) re-used ubolts.

andrewmp6

I didn't know a u bolt had a torque to number and i have reused them also.

cruiser54

we're doomed andrew.

andrewmp6

I have reused head bolts because i was stuck in a pinch and the motor still runs fine.Or a driveway alignment with a long enough piece of string or rope a few times.But i have always owned old junk you can get away with a lot more then a modern car.