Rear end carrier bolt broke please help!

Soundkillr · #1 (**permalink**) 02-11-2022, 12:30 PM

Rear end rear carrier bolt broke...please help

Guys took my backdraft out for a run today and got on it in 3rd. I hear a load bang in the rear end...and now something is striking somewhere making loud banging noise and sounds like axles scrubbing something.I noticed the lower carrier bolt as picture is sheared off and the end of the carrier where the bolt goes looks to be broken. Can anyone guid me on what to do? Can anyone send me pics of what its supposed to look like? It also appears the drive shat has moved out fron the transmission 1/8 of an inch.

Woukd thus broken bolt be my issue or should I look other places as well.

Grubby · #2 (**permalink**) 02-11-2022, 02:29 PM

I would fix the obvious broken bolt and taken for an easy test drive to confirm no other problems exist.

John

bobcowan · #3 (**permalink**) 02-11-2022, 02:56 PM

That seems to be a common thread in high powered BMW's and BDR's. As soon as I get a chance, I'm going to install a support bracket there.

https://store.activeautowerke.com/co...racket-dsb-e36

Soundkillr · #4 (**permalink**) 02-11-2022, 03:33 PM

Quote:

Originally Posted by bobcowan

That seems to be a common thread in high powered BMW's and BDR's. As soon as I get a chance, I'm going to install a support bracket there.

https://store.activeautowerke.com/co...racket-dsb-e36

Nice to hear...and im going to check that link. Ive manager to realign the diff...but need to drill the broken bold out.anyone have any experience doing this? Im obviously going to work from the rear of the car facing forward....and see if I can bring the broken bolt toward me and remove it that way...

SBSerpent · #5 (**permalink**) 02-11-2022, 08:16 PM

What HP is your motor? And what motor is it?

Peaked my interest since I have a BDR with the same rear. My motor is a 392 rated at 420HP

Soundkillr · #6 (**permalink**) 02-12-2022, 06:12 AM

Quote:

Originally Posted by SBSerpent

What HP is your motor? And what motor is it?

Peaked my interest since I have a BDR with the same rear. My motor is a 392 rated at 420HP

It's got a built 428fe supposed to be making 550hp and a ton of torque...
IF these reinforcement brackets will fit id recommend getting one...

Soundkillr · #7 (**permalink**) 02-12-2022, 06:15 AM

Quote:

Originally Posted by bobcowan

That seems to be a common thread in high powered BMW's and BDR's. As soon as I get a chance, I'm going to install a support bracket there.

https://store.activeautowerke.com/co...racket-dsb-e36

Im definitely looking into this kit. Can anyone confirm it will fit our cars? I know it would obviously fit the diff housing...but will it work with our rear cradle? Or does the backdraft use the same cradle support as the bmw?

Also...anyone have any suggestions on how to get the broken bolt out?

bobcowan · #8 (**permalink**) 02-12-2022, 10:24 AM

Drilling that bolt out is going to be a real PITA. Can you even get a drill in there? You may have to buy a small right hand drill fro access. I don't have my car with me, so I can't go out and look.

Use a center punch, and make a big dent with multiple taps. Start with a small bit, like 1/8" or so. Go slow, go straight, and use plenty of oil.

When the hole is big enough, tap in a course rat tail file. Turn it out with a pair of vice grips. Be sure and use plenty of penetrating oil, like PB Blaster.

It will probably be easier to push it back out the way it came in. There's probably a burr where it broke, and that burr will hang up on the threads.

FredG · #9 (**permalink**) 02-12-2022, 11:12 AM

After you posted this, I looked these up. There are some out there that are a lot less expensive. This could be another future upgrade in the making.

Fred

Quote:

Originally Posted by bobcowan

That seems to be a common thread in high powered BMW's and BDR's. As soon as I get a chance, I'm going to install a support bracket there.

https://store.activeautowerke.com/co...racket-dsb-e36

Grubby · #10 (**permalink**) 02-12-2022, 11:46 AM

I like to use LH twist drill bits to drill out bolts. It tends to back them out while you are drilling.

Other than that do as Bob suggested above.

John

169mph · #11 (**permalink**) 02-12-2022, 02:20 PM

Quote:

Originally Posted by Soundkillr

Rear end rear carrier bolt broke...please help

Guys took my backdraft out for a run today and got on it in 3rd. I hear a load bang in the rear end...and now something is striking somewhere making loud banging noise and sounds like axles scrubbing something.I noticed the lower carrier bolt as picture is sheared off and the end of the carrier where the bolt goes looks to be broken. Can anyone guid me on what to do? Can anyone send me pics of what its supposed to look like? It also appears the drive shat has moved out fron the transmission 1/8 of an inch.

Woukd thus broken bolt be my issue or should I look other places as well.

I had the same thing happened last month. Same Bolt sheared. I’m trying unsuccessfully to extract the end of the bolt out without dropping the differential. Tried to use a dremel tool to cut a groove in the end of the bolt so I could back it out with a flat head. Couldn’t cut a groove deep enough. I think lm going to drop the differential and replace the bushings and upgrade the front bolt.
Thanks Mike

twobjshelbys · #12 (**permalink**) 02-12-2022, 02:50 PM

What spec bolt???

Mongoose930 · #13 (**permalink**) 02-12-2022, 03:48 PM

I've actually had pretty good luck with this type extractor:

https://www.amazon.com/Irwin-Industr...4706024&sr=8-4

Sledge · #14 (**permalink**) 02-12-2022, 03:54 PM

I installed the Active Autowerke diff support in 2010 and have not had a problem with broken rear end parts...at least not yet!

Soundkillr · #15 (**permalink**) 02-12-2022, 05:35 PM

Quote:

Originally Posted by 169mph

I had the same thing happened last month. Same Bolt sheared. I’m trying unsuccessfully to extract the end of the bolt out without dropping the differential. Tried to use a dremel tool to cut a groove in the end of the bolt so I could back it out with a flat head. Couldn’t cut a groove deep enough. I think lm going to drop the differential and replace the bushings and upgrade the front bolt.
Thanks Mike

Sorry to hear...this is my thought...if you want to try it....im goingnto take a thin copper sleave to protect the threads...then im going to weld a small nut on the back of the broken bolt.....then im going to try and run the bolt forward toward the car. Hopefully this will work...but it will be about 3 weeks before my buddy can help me.

They only drill I could see fitting in that area would be a pneumatic 90 degree drill with a thin chuck. And even then I wouldnt be able to drill straight in for an extractor. If anyone else is dealing or has dealt with a broken bolt...what method worked?

Id rather eat bugs than drop thus differential.

Soundkillr · #16 (**permalink**) 02-12-2022, 05:39 PM

Quote:

Originally Posted by Sledge

I installed the Active Autowerke diff support in 2010 and have not had a problem with broken rear end parts...at least not yet!

Was the install easy? Does the lower cradle plate have threads in it for the two bolts to sandwich it down? Im trying to fgiure out how the two lower bolts attach.....and I would assume the upper cradle plate is threaded...

I see no bolt holes in the front carrier to accommodate the two bolts in the kit.

Soundkillr · #17 (**permalink**) 02-12-2022, 06:03 PM

Quote:

Originally Posted by 169mph

I had the same thing happened last month. Same Bolt sheared. I’m trying unsuccessfully to extract the end of the bolt out without dropping the differential. Tried to use a dremel tool to cut a groove in the end of the bolt so I could back it out with a flat head. Couldn’t cut a groove deep enough. I think lm going to drop the differential and replace the bushings and upgrade the front bolt.
Thanks Mike

So heres the method im going to try and follow...

https://youtu.be/-8N0y0jVAng

Fast forward to the five minute mark to see what im trying.

SBSerpent · #18 (**permalink**) 02-12-2022, 07:44 PM

Quote:

Originally Posted by Soundkillr

Sorry to hear...this is my thought...if you want to try it....im goingnto take a thin copper sleave to protect the threads...then im going to weld a small nut on the back of the broken bolt.....then im going to try and run the bolt forward toward the car. Hopefully this will work...but it will be about 3 weeks before my buddy can help me.

They only drill I could see fitting in that area would be a pneumatic 90 degree drill with a thin chuck. And even then I wouldnt be able to drill straight in for an extractor. If anyone else is dealing or has dealt with a broken bolt...what method worked?

Id rather eat bugs than drop thus differential.

I used this very same method to extract a broken exhaust manifold bolt on a 460 BB where the shaft of the bolt was barely proud of the surface of the manifold. Work perfectly. You should have no problem with this method. Bolt will come out easily.

Soundkillr · #19 (**permalink**) 02-13-2022, 06:53 AM

Quote:

Originally Posted by SBSerpent

I used this very same method to extract a broken exhaust manifold bolt on a 460 BB where the shaft of the bolt was barely proud of the surface of the manifold. Work perfectly. You should have no problem with this method. Bolt will come out easily.

Thanks man....and thats what im hoping. I really think this will be the best method for success. I just hate having to wait three weeks for my buddy with the talent to show up. Lol.

Sledge · #20 (**permalink**) 02-13-2022, 07:53 AM

Sound: The install was pretty easy I did it myself. The instructions for installation are available at the Autowerke link provided by Bob Cowan, and in the form of a downloadable .pdf file (contains words and lots of photos).

Cheers