The rear end is rattlin' like a tin can full of rocks.....

[ksjdan]

Wow. Found my problem.....



How the heck do TWO of these bolts get loose and come off? especially from the top! I had to drop my rear a few months back when lowering the car. I did have a highly recommended BMW shop do it....crazy.

So now i'm in need of these two bolts...any one know what size these might be? Should I use loctite?

Diff bolt backing out seems to be a common problem among newer model BMWs. Didn't know e30s do this too.

[Klug]

Took a look over everything else after putting about 20miles on it. Bolts looking fit and bushing are all in good shape. I'm going to keep an eye on these over the next few weeks and make sure they are not coming loose. I was going to use loctite but I didn't want to use it if I didn't have too.

Not sure why they removed those bolts to put in springs.

When I was installing my coilovers via Pellican's DIY it requires you to lower the rear diff by removing the two (even though my '89 has four) bolts that hold it up.

[Cronopoulos]

Mine did the same thing, also retrofitted new hardware with blue loctite. Glad you got the problem handled... that could have potentially gone a lot worse down the road..

[Klug]

Update.

So after putting in the two bolts, it seemd that all my problems went away. Then today I'm driving and start hearing a clunking in the rear when engaging 1st and 2nd gears. Sounded like the CSB was going. Went down under and found out now the other two top mounted bolts were loose...and my new bolts were not as tight as they were a few weeks ago.

Should I go the loctite route or take it in somewhere to get it air-tool'ed down to the right torque rather than just hand tightening them down. I feel this is going to keep happening.

Does everybody run into this problem when they've removed the rear?

[MDVDuber]

Loctite is a fine idea - but just buy yourself a good torque wrench and do it yourself.

[jlevie]

The use of blue Locktite and/or torquing the bolts to spec should do it. Unfortunately to torque the bolts to spec you will have to drop the subframe.

[AndrewBird]

You might have something in the drivetrain that is out if balance, causing a vibration, and causing the bolts to loosen. Do you have any other vibrations?

[Klug]

You might have something in the drivetrain that is out if balance, causing a vibration, and causing the bolts to loosen. Do you have any other vibrations?

Well after tightening the bolts down using my MAX ARM STRENGTH, I've driven on it for over 300miles and so far everything is still tightened down. So far so good, with no other vibrations currently.