https://ls1tech.com/forums/gears-axl...destroyed.html
here is the original post. this is not intended to rip umi or any other sponsor. this is strictly to find solutions to the problem, even though i am still upset.

after digging into the after-math of the broken torque arm, i also have a damaged driveshaft, and the rear quarter panels on car on both sides were wore out by the rear tire, over a part that SHOULD NOT have broken in the 1st place. let me remind everyone, the car is on 19in. street tires NOT drag radials.

after taking beginner classes at the race shop on how and why it broke, my first thought is it is not moser's fault.....although i understand a bolt all the way thru would have been the smart thing to do, i believe i can PUT A BOLT WITH A LOCK WASHER ON IT (by itself) AND IT WILL NEVER COME LOOSE BY ITSELF. therefore leading me into the next part of the problem.
WHAT IS MAKING IT COME LOOSE?
i believe it to be a 3 part problem
#1 as stated by tillery, the bolt holes for the 12 bolt are way to big, so i'm assuming the reason for this is the holes are pre-drilled because 10 bolts and others have bigger bolts? if this is the case maybe umi should have different brackets made for different rear ends? bolt holes in 12 bolt being to large are causing small movement in bracket causing bolts to back out. not a moser problem.

#2 blackduk98 showed everyone on here there is not nearly enough metal on bracket to hold the pressure that the torque arm hole could possibly see. there is plenty of extra room on the 12 bolt for more metal. is it possible that umi has the "cut" in the bracket so it will be universal for all the rear ends? wouldn't it be a safer fix to make a different bracket for the 12 bolt if this is a reoccurring problem? and i quote "i receive 3 phone calls a day with guys with 12 bolts having the same problem as me"

#3 quoting your own website
i believe you are using the same bracket and holes for all the rear ends based on this quote, even though i could be wrong. it says NO WELDING, but i've been told several times by umi now, quote "you will need to tack weld bolts" this is not a fix after talking with the weld guys, but a band aid. the tack weld is still gonna break, therefore causing the bolt to back out.

 

the solution

my whole suspension is umi. i think it is a good product, but with anything, sometimes improvements can be made.

#1tillery offered one suggestion of putting in some sort of spacer/bushing to take up space.
#2blackduk98 and i can confirm the space for the metal and outer edge is way too close, and that is exactly where mine ended up breaking, even though that's not what started the problem. i believe the holes being too large caused extra space and allowed back and forth movement on bracket whick slowly backed the bolts out. bolts were not the issue in my case, they were supplied by umi, and were not bottomed out as some were suggesting.
#3 i have a part solution. i believe umi should make a bracket ONLY for the 12 bolt design which would have the extra metal in place, and smaller holes.............specific 12 bolt bracket, extra metal on bracket, smaller holes.

 

customer service has not/ever been an issue. however i do believe after receiving my new torque arm, the bracket is essentially exactly the same as the old one. i WILL take some steps to try to avoid this happening again. (some sort of bushing), checking to make sure they are tight every 3 to 5 thousand miles, probably some sort of lock tite.

HOWEVER,
if this happens again, i will be very, very, upset...............considering it should not have happened to start with....then being told it happens 3 times a week, and the fix is some sort of welding that your website says i should not have to do, and everyone now realizes there is some sort of a problem and there is a fix if someone there is willing to try.

 

Good post. I tend to agree with what wvaboy has said. Not blaming Moser, or UMI, which both make a good and quality product for our cars, but I beleive that if UMI is going to advertise that this torque arm works with a Moser 12 bolt, then they should stand behind their product if it breaks and not try to blame it on Moser.



While I agree with the torque arm bolt setup not being the best design on Mosers part, I do not agree with UMI blaming it on the Moser bolt setup. If you are going to advertise the torque arm to work with the Moser 12 bolt, then it should work with the moser 12 bolt. No modifications should have to be made to the torque arm (bushings for the bolt holes, welding, etc) and if so, the bushings for the wholes should be supplied with the kit.

Like said previously, this is not intended to bash Moser or UMI, but I think this is an issue that needs to be addressed.

 

The Moser bolts coming loose are very common... again we never blamed Moser but we have seen this happen on a few occasions with our torque arm AND other brand torque arms and only with the Moser 12-Bolt. We do feel Moser's design is the cause of this. For some reason we are always told to make our torque arm fit better with the Moser 12-bolt and you guys have no problem telling us this. Why not call Moser up and discuss this issue with them? Has anyone done that?

We do not feel it is necessary to change our design... we are 100% sure the issue is caused by the Moser 12-Bolt rear end. It will fit and work perfectly fine on the Moser 12-bolt but does require you to take extra precautions to insure it stays tight. These extra precautions are listed in a waring of the instructions.

We sent the original poster a new bracket for his torque arm free of charge so he could sell it. We also sold him a new torque arm at a discount. The design of the bracket was not changed because we only feel this issue occurs with Moser 12-Bolt rear ends. We have thousands of torque arms on the market and many on single digit cars. This issue has only occurred on a Moser 12-Bolt rear end. Out of the thousands of torque arms only a 3-4 rear mounts have broke, all on Moser 12-Bolts and all the users told us when they crawled under the vehicle the bolts were either loose or missing...

I am not trying to start a argument but I do like to explain why we do it the way we do.

Hope you understand,
Ryan

 

The torque arm does work just fine with the Moser 12-Bolt... there is no fitment issues on the torque arm. There are no modifications needed. The welding is a recommended precaution for the user... do to there design we highly recommend to tack weld the bolts in place to prevent this issue. You can also wire the bolts together.. but we found welding to be easier. If you want to crawl under the car on occasion and check the bolt tightness then welding wouldn't be needed. But I feel there is no wrong with us recommending precautions for the user to take? Moser does use much smaller than factory bolts, spacers are a good idea to take up the bolt slack. But why does Moser not supply spacers with there rear ends? Just a thought...

Thank you,
Ryan

 

Are you referring to us telling you this happens 3 times a week? We never said that if you are... it has happened 3-4 times total over 5 years. Sorry if I mis-understood... if I did please correct me. But that is false. Also welding is NOT needed... but to prevent this issue and prevent you from crawling under the vehicle every few thousands miles this was a precaution we recommended. If I would have known we were going to get so beat up over recommended tack welding a few bolts we would have never recommended it....

 

The Problem, IMHO is the moser, plain and simple, and why they had to do a bolted design. I broke two torque arms because of that stupid rear. But I broke a bmr about 8 times in several different places, repaired it so many times I was sick. The hole sizes is not the issue I can assure you, because at one point, I made my own bracket with the exact same size holes as the bolt and it still cracked, initially I welded a bead arount the holes to close them up, same prob. I tried loctite, lockwashers nothing helped. Finally I drilled a hole and used lock cables like an aircraft uses to keep the bolts from backing out, that was the only thing that worked for me. Eventually, since I have all the equipment anyways, I built my own arm out of 4130 and it has held up since. But, the size of the hole does not matter if that bolt loosens, it just elongates the hole, and then bends, then snaps that plate. Or, you could just check the bolts every couple weeks, but that is a pita.

Everything that I do have of UMI's is top notch... it's not their faulty manufacturing here.

 

400.00 shipped so lets not stretch it. money isn't the issue here anyway, so let's not go there. i do appreciate the free shipping and discount that was given, and i mentioned customer service is NOT an issue. i believe more r&d could be done for this. the bolts are coming loose because over time the bracket is moving back and forth causing the bolts to loosen, then damage the drilled holes until either bracket breaks or bolts come all the way out.
I WILL BE CALLING MOSER THIS WEEK ALSO. even though i already know they will tell me there's nothing they can or will change with there product.
i go back to what i said before, if i put a bolt with a lock washer in the rear, by itself, it's probably not coming out.

i just don't want this to happen again, because it did do more damage than just a bracket.

ryan, just out of sheer curiousity. do you use universal brackets? (one bracket pre-drilled for all rear ends)

 

this is more good info.
i can assure you, i will never buy a moser 12 bolt again! i do think umi stuff is top notch, my whole car is covered in it. i'm just wondering if a different bracket for this rear would work.

 

Thanks for understanding and just like you said, I am not trying to argue either... just discuss. Yes we sell one bracket for all rear ends and this bracket works very well on all rear ends with the exception of the Moser 12-Bolt. All Strange rear ends and the Moser 9" all use the stock style mounting holes and design. If we made a bracket strictly for the 12-Bolt we could shrink the holes but I don't know if this would help much since the issue is the bolts actually coming loose and not moving. The holes we supply in the bracket now are drilled to the factory hole size. You can't add to much more material to the bracket because then it won't slide on the rear end properly. It is just one of those rear ends you need to check.

Hope that helps!
Ryan

 

Since this is a problem with the 12 Bolt, why not make just a bracket with the correct bolt hole sizes and a little bit more meat? There is room on top and deffinately on the bottom for at least another .250 of material. I undersatand that they bolts may and probably will back out, but the material should not break. There is just not enough material there to hold alot of force. Just a suggestion.



My reasoning for moser for not sending the spacers for the torque arm bolt holes is because moser does not make torque arms. They made a 12 bolt work for the f-body, then UMI made a torque arm to work on a 12 bolt in an Fbody. I believe that if you are going to recommend that with a 12 bolt (washers, spacers, tacking, etc) are needed, then they should be included with the torque arm.

 

But there 12-Bolt also works with the factory torque arm and this does happen with the factory torque as well. The difference is the factory torque arm bends since the material is so thin, rather then breaks.

The issue is the bolts coming loose and not so much the hole size.. although I still feel it was not a good idea on Moser's end to shrink to a 1/2" bolt from 14mm. We can't add anymore to the bracket because then you will be grinding the housing or bracket to get them to fit. We noticed a variance is Moser's casting and have had to grind the casting to get our arm to fit.

Keep your bolts tight, lock tight, lock washers whatever works best for you. If you can wire the bolts or have them tack welded at some point this is best. This will prevent any issues.

Ryan

 

Ryan,

Thank you for taking the time to discuss this matter, and keeping it from getting into a pissing match.

One more question though, Do you not believe that the reason that the bolts are coming loose are due to the bolt being much smaller than the hole, and the bracket "walking around" on the rearend? If the braket has any slight movement to it, it seems that it would wear through the powdercoat, and eventually into the bracket causing it to loosen up. In this perticular case, all the bolts were still in the rear end housing, after the top back bolt hole broke, it just bent the bottom bracket due to the force.

 

I still can't believe you aren't using safety wire with those bolts.

If you think a lock washer should keep a bolt from ever backing out, you are sorely mistaken.

 

Has anyone thought about using studs? Would that help things any?

The reason I ask this is on cylinder heads some people use studs because the clamping force is better.

You could put the torque arm on the rear end then put the studs in, most studs have a hex in them to thread them in. Use loc tite on that side of it.

Then use lock washer with nuts and/or lock nuts. I think bushings would be a good idea to help things keep from shifting around.

Just my .02

 

Weld a thick washer [same size as the bolts] over the holes use longer bolts +locktite and your good to go.

 

Studs might work, but of course have to install after arm is in place. Over torqueing is still an issue that stresses the material. Alot of people are doing this and cracking the mount. if the mount is drilled for the Moser rear and correct torque,lock wire, locktight. Or what ever is used is done correctly. All these sponsers make great products. But with improper instalation. Anything will fail. Would be great if Moser would chime in to explain thier design. Maybe its becaue the mount is just that. Not intended for doing the work of the whole TQarm.

 

yea i don't think moser has any reps on this site or any site that i know of. Next best person to get some info out of would be Bob at EPP. He has sold over 1million dollars worth of moser rearends and I believe he picks his orders up straight from mosers factory. So maybe he could get some info out of them as to why they chose a four 1/2" bolt design over a factory design.

I mean mosers 12bolt center was designed for 3rd and 4th gen cars. Why would you change what already worked(2 14mm bolts)?

 

If they supply 4 bushings with there TQ arm or sale them without the arm for 12bolt rearend's all this blaming everybody would be over......