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Uh...you might want to tighten those U-bolts...

4speedfunk

Well-Known Member
Messages
4,212
Location
Tardville
So this morning I'm out for my morning run, when a buddy of mine drives past me in his Fummins (2004 Ford F350 with a 12v Cummins diesel). I waved and he proceeded to turn onto the main highway...when I heard a horrendous noise. As I ran back to the intersection...he had pulled over and was looking underneath his rig. I came up on the situation to see if I could lend a hand. The rear axle housing was rotated...YOKE STRAIGHT UP! It looked like a freakin Rockwell!!!! I said, "Dude...your U-bolts are loose". He said that entire axle was brand new, (it was all painted nice & purdy). I said "not anymore". (yeah I tend to be a sarcastic SOB). He went on to say he just got it together, and only had a few miles on the new axle. This truck had ridiculously large 5" lift blocks in the rear, and they had large chunks missing from them.

So he gets inside and power-brakes it in reverse to point the pinion back to something close to normal. I grabbed some wrenches and we got the U-bolts tight...but the rear U-joint was toast, as was the end of the driveshaft and possibly the flange where it bolts to the pinion. He limped it over to my driveshaft guy for a not-so-quick (and not so cheap) fix. I recommended that he do a shackle-flip instead, and run some arched springs instead of those big goofy blocks. The Jamboree is in Indy this weekend and he was on his way up there...clearly he may have been in a rush during the final assembly. tsk tsk.

So, for those of you that have done the SOA mod (or any other fiddling with U-bolts) on your H3....take some time to re-torque the U-bolts after you drive it for a day. You might be surprised how much they can loosen up, and you can avoid a lot of serious damage by just doing a quick re-check.
 

07Custom

Well-Known Member
Messages
338
Location
Albuquerque, New Mexico
So this morning I'm out for my morning run, when a buddy of mine drives past me in his Fummins (2004 Ford F350 with a 12v Cummins diesel). I waved and he proceeded to turn onto the main highway...when I heard a horrendous noise. As I ran back to the intersection...he had pulled over and was looking underneath his rig. I came up on the situation to see if I could lend a hand. The rear axle housing was rotated...YOKE STRAIGHT UP! It looked like a freakin Rockwell!!!! I said, "Dude...your U-bolts are loose". He said that entire axle was brand new, (it was all painted nice & purdy). I said "not anymore". (yeah I tend to be a sarcastic SOB). He went on to say he just got it together, and only had a few miles on the new axle. This truck had ridiculously large 5" lift blocks in the rear, and they had large chunks missing from them.

So he gets inside and power-brakes it in reverse to point the pinion back to something close to normal. I grabbed some wrenches and we got the U-bolts tight...but the rear U-joint was toast, as was the end of the driveshaft and possibly the flange where it bolts to the pinion. He limped it over to my driveshaft guy for a not-so-quick (and not so cheap) fix. I recommended that he do a shackle-flip instead, and run some arched springs instead of those big goofy blocks. The Jamboree is in Indy this weekend and he was on his way up there...clearly he may have been in a rush during the final assembly. tsk tsk.

So, for those of you that have done the SOA mod (or any other fiddling with U-bolts) on your H3....take some time to re-torque the U-bolts after you drive it for a day. You might be surprised how much they can loosen up, and you can avoid a lot of serious damage by just doing a quick re-check.

TRUE TRUE TRUE. After my SOA I drove it for a few days and went to check the U-bolts and they were definitely looser than when I torqued em. Not dangerous but I'm sure it could have gone that way!
 

4speedfunk

Well-Known Member
Messages
4,212
Location
Tardville
AHHHH... good. When I saw this guy's Ford....I immediately thought of you. Always better to learn from some other guy's mistake!
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
Haven't that that issue but I torqued the **** out of them when I did mine....probably a bit too much but id rather over tighten then have that issue!
 

Hunner

Well-Known Member
Messages
2,334
Location
Arkansas
There are several responses to that straight line but I will resist!!! lol
6xTorqueSpecs-1.jpg

For us it could look like this

 
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06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
how so? Causing issues with the leaf springs and allowing movement?

I have been running my spring over for over a year and 20k miles with no issues. I did make the mistake of not changing my 95k mile bushings when I did the install and need to be replaced so I may do that soon. I will get new U bolts and properly torque then...
 

4speedfunk

Well-Known Member
Messages
4,212
Location
Tardville
I wish I had my camera on me this morning....it was quite a site.

I'm not up to snuff on my late-model parts but, I think it was a big Sterling or possibly some some sort of mega-duty Dana 70,80,90 whatever. Anyway...it really was cool to see something that big & heavy floppin around like that. The pinion flange & end of the driveshaft were totally ganked. I'm not sure how the housing rotated that far but, there's no question those huge lift blocks played a part in it.

By the way...if you think axle wrap is a joke or you don't understand exactly what it is? Check this out....

https://www.youtube.com/watch?v=Hv6HZVv4GUo

Unlike the rig in this video...this guy's issue wasn't the springs, it was loose U-bolts. But the effect is the same.
 

SuperBuickGuy

Well-Known Member
Messages
3,403
Location
Woodinville, WA
how so? Causing issues with the leaf springs and allowing movement?

I have been running my spring over for over a year and 20k miles with no issues. I did make the mistake of not changing my 95k mile bushings when I did the install and need to be replaced so I may do that soon. I will get new U bolts and properly torque then...

overtightening stretches the bolt - which will cause bolts to eventually break. A loose bolt will move around, an overtightened bolt will pop at the worst possible time.
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
I have seen that video. That is why I was worried about axle wrap before I did the spring over. For H3s axle wrap is not an issue like the jeeps have. There short wheelbases and soft springs probably play a role in that. A simple traction bar will fix that and avoid the pinion rotating up like that video showed. I just hate the thought of a traction bar as its something that can get in the way of rocks and just cause more hangups on offroad, I also wonder if a traction bar affects flex too....Not sure, I will have to research that but I assume it might as its just another thing to bind on.

That is one pro of a very modern 4link and panhard bar or 3 link and panhard bar. They wont let the pinion rotate like that...Lift blocks exaggerate the axle wrap. There are those guys running 8in lifts on big diesels with stock springs big lift blocks and big power. Its scary what axle wrap can do to a rig like that. I see a lot of huge chevys running traction bars to help that issue, most are mall crawlers and 2wd around here in poserland so cal.

Thanks for the heads up superbuick. I may replace mine sooner then later and even keep a spare or two. I understand the damage would already be done but atleast you could tow off the trail if you atleast had your suspension connected to the axle!
 

4speedfunk

Well-Known Member
Messages
4,212
Location
Tardville
I think I got some minimal axle wrap going on mine. I recently had an issue with the slip yoke sticking to the output shaft of the t-case. It occurred to me after watching a few of those videos, that I probably got quite a bit more than what I think...otherwise I wouldn't have that much movement at the yoke. I'm terrified to strap my GoPro under there. Not terrified for the camera....but terrified what I might catch on film!

Lots of Jeep guys around here run WFO Concepts torque arms. I think thats sort of their bread & butter product. I might look into adding one to my rig....looks simple enough:

http://www.wfoconcepts.com/pr/Torque-Arm-Kit-3-375-Dia-Axle-Tube/4140/3994

http://www.wfoconcepts.com/Uploads/Additional_pictures/Torque_Arm_additional_pictures_2.jpg

I'm sure you can get torque arm kits anywhere but, WFO has quite an assortment available. Couple hours of welding might be worth it.
 

06 H3

a.k.a. "The Jackal"
Messages
9,350
Location
Meridian, ID
I need to get a go pro and see the difference between both driveshafts in and 4hi unlocked vs only rear driveshaft and 4hi locked. Huge difference! h3s have soft springs which is a part of the recipe for axle wrap but I truly believe the division of power makes up for it.

I have driven with no front driveshaft in and all the power going to the rear...you can feel the axlewrap much more. With both shafts on and in 4hi or 4lo I barely notice it
 

alrock

El Diablo
Staff member
Messages
10,442
Location
Scottsdale
Couple of things, and correct me if I'm wrong: 1) torqueing bolts, especially items like u-bolts, is designed to stretch the bolt to use tension lock it in place and 2) some bolts, like u-bolts, don't respond well to multiple uses as the proper stretch/torque ability is diminished. It’s the elasticity of the steel trying to pull itself back to its original length that allows a bolt to provide a consistent clamping load

As you can see from this video, even though you achieve the proper torque with an old bolt, you don't necessarily achieve the proper tension, though this video talks more about rust, etc. on a bolt.
[video=youtube_share;O96AUlIBkU8]http://youtu.be/O96AUlIBkU8[/video]
 

Expendable

Well-Known Member
Messages
1,025
Location
Burbank, CA
I need to get a go pro and see the difference between both driveshafts in and 4hi unlocked vs only rear driveshaft and 4hi locked. Huge difference! h3s have soft springs which is a part of the recipe for axle wrap but I truly believe the division of power makes up for it.

I have driven with no front driveshaft in and all the power going to the rear...you can feel the axlewrap much more. With both shafts on and in 4hi or 4lo I barely notice it

Kyle has a GoPro Hero 3 (pretty sure black edition) and I have a GoPro Hero 2.

between the two of us we should be able to help if you so wish.
 
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