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Discussion Starter · #1 · (Edited)
Today turned out to be one of the worst days I have had in a while. I was driving home from work, and as I took off from a stoplight I hit first gear then when i put it into second I heard a huge clunk. I look in the mirror and see metal pieces flying all over the road and I feel a weird vibrating. So I get out and look under the back of the car and notice that the Diff was sitting about 4 inches lower than it should be and the wheels have an extreme amount of negative camber and that the fins on the bottom of it are completly gone, which is wat was all over the road. So I limp it home with the hazards on in first gear. I think that the diff broke away from the subframe im not sure it was too dark when I got home. So i will look at it when I wake up. But has any one else had the problem where the diff breaks away from the subframe?
 

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Have you checked the subframe at all since you had the car ?

Also I know someone that may have a stock diff cover for sale...but I expect that will be the least of your wories if you've pulled the diff mount out of the car.
 

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Officially Weird
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Wow, the diff broke away entirely from the subframe? That's gotta be no easy task. It's bolted to the subframe pretty well.
 

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You can call or E-mail me, if you have any questions: 419 350 1098 or [email protected]

I've seen a few bad ones...





























Poorly repaired by others:









After I finished:













The complete albums for all these jobs, and many more like them, can be seen at: www.spcarsplus.com/gallery
 

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Somebody's not been doing their monthly "how does my diff mount/trunk floor look" checks.

I guess we could fab up a temp support for the Diff if you plan to take it over toledo.

Send me a PM if you want some help.
 

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The third picture in randys post is exactly what happened to mine and almost exactly what mine looks like.
Why would a broken diff hanger cause the diff to drag on the ground? I don't know about you guys, but on my car the diff is mounted to the subframe with quite a few bolts, which is in turn mounted to the car via the big subframe bolts.

Something else major would have to fail for the diff to hit the ground. Mine's a good 6" off the ground.
 

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Why would a broken diff hanger cause the diff to drag on the ground? I don't know about you guys, but on my car the diff is mounted to the subframe with quite a few bolts, which is in turn mounted to the car via the big subframe bolts.

Something else major would have to fail for the diff to hit the ground. Mine's a good 6" off the ground.
With the stock subframe bushings, pulling out the rear bolt (in the cover) will allow the differential to drop several inches.

Here's a static example, so imagine (as stated in the original post) dropping the clutch and letting the torque twist it a little lower...

 

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Thanks. I did not realize the diff could droop that much once disconnected. It already looks like the half-shafts are already angled downwards, although that might just be due to suspension compression (looks like the RR spring is squashed). I can imagine under acceleration that the torque could twist the diff quite a bit, especially since the pivot point would be way up at the subframe mounting studs. I'd expect the studs to bend at that point, too.

I guess I just didn't realize how much it drooped because when I pulled mine it was being supported, naturally, by a jack :)
 

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Diff is well bolted to the Subframe but with stock bushings if you disconnect the diff bracket there is plenty of movement allowing the subframe to rotate and the diff to drop, add in being under power and you have a really nasty situation.
 

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My diff bracket just snapped off yesterday afternoon. Fortunately I was pulling out of a parking lot at low speed & power so it didn***8217;t hit the ground. I had a tear a couple of years ago that I put a temp repair in place until I could afford to buy Randy***8217;s kit. Guess I wait too long (understatement of the week) and didn***8217;t listen to the car when I thought it felt a little funny over the last week or so. So much for heeding the warning signs.

I have been trying Randy***8217;s web site(s) but they seem to be down. I did send him an email so hopefully all is ok with him and he still has some parts on the shelf. Driving my wife***8217;s 3 series for now until I can break out the welder this weekend.

The lessons learned: Temporary should never be left on permanently and if it feels different it likely is different, find out why....

Chris
 

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Thanks. I did not realize the diff could droop that much once disconnected. It already looks like the half-shafts are already angled downwards, although that might just be due to suspension compression (looks like the RR spring is squashed). I can imagine under acceleration that the torque could twist the diff quite a bit, especially since the pivot point would be way up at the subframe mounting studs. I'd expect the studs to bend at that point, too.

I guess I just didn't realize how much it drooped because when I pulled mine it was being supported, naturally, by a jack :)
Makes it easy to get out the springs by dropping it.
 

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A camaro would be best for launching from stoplights. I baby mine from starts. Too long a drive to Ohio for me.
 

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My diff bracket just snapped off yesterday afternoon. Fortunately I was pulling out of a parking lot at low speed & power so it didn't hit the ground. I had a tear a couple of years ago that I put a temp repair in place until I could afford to buy Randy's kit. Guess I wait too long (understatement of the week) and didn't listen to the car when I thought it felt a little funny over the last week or so. So much for heeding the warning signs.

I have been trying Randy's web site(s) but they seem to be down. I did send him an email so hopefully all is ok with him and he still has some parts on the shelf. Driving my wife's 3 series for now until I can break out the welder this weekend.

The lessons learned: Temporary should never be left on permanently and if it feels different it likely is different, find out why....

Chris
Update on Randy; he replied quite quickly to my email. Seems he is fine and in business. His web site hosting company moved offices and they are having problems getting back on-line.

Chris
 

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A camaro would be best for launching from stoplights. I baby mine from starts. Too long a drive to Ohio for me.
If a $42000 sports car has to be babied from fast starts but they are ok in a camaro, the BMW engineers need to go to the same school as the camaro designers...Cheap welds & cheap metal should never be a part of the equation at these prices

Just my humble opinion

Chris
 

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I can't see Randy's pictures with his 8-4-09 post.
Is anyone else having that problem?
His web site that hosts those files is temporarily down. Once that gets fixed (currently being worked on), the pictures will come back

Chris
 
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