Diff fit question

[bimas]

As some of you know, my Jim Blanton LSD has locked up. Interestingly enough, the damage has occurred most likely from within the clutch pack! I am looking for a suitable replacement for the time being, as repairing the JB diff seems very cost prohibitive right now.

I have already bought new axles, before my shop informed me that the diff is dead.

A have a couple of leads for M5 diffs, but here are my questions/concerns:

My diff is flanged for 540. The M5 has larger flanges (94mm vs 102?). Do I need to use M5 axles with the M5 diff? Or, alternatively, can I swap 540 flanges onto the M5 diff?

Any other concerns? Am I completely off the rocker?



Sorry, if I am asking stupid question. I know how all of this is done on E30 an E24.

[BimmerBreaker]

just kidding, i guess!

[bimas]

540 flanges can be swapped into the M5 diff to use the 540 axels.
Thanks for a quick response. So, me and an air torque gun can do it just like on the E24?

[JimLev]

540 flanges can be swapped into the M5 diff to use the 540 axels.

No they can't, the locking ring is in the wrong location.
540 flanges will pop out of the M5 diff if you try to use them.

See post #9 for info.
http://www.bimmerforums.com/forum/showthread.php?1767892-E39-M5-limited-slip-differential-swap-into-an-E39-540i

[philly98540]

Is the JB differential based off a 540 or M5 diff? The M5 diff is a bit longer and takes shorter driveshaft.

If you switch to a M5 diff, you may need to get a M5 length DS.

[bimas]

The JB is based on a 540 diff. I know this, because I compared the new drive shaft to the old, and it's a match. As far as I know, I need the V8 E31, 32, 34, 38 and E28 M5 flanges. It's P/N: 33131214087. Anyone selling a pair? As far as the drive shaft goes, I need the M5 one or just M5 rear shaft and a rebuild/balance. This route seems easier and more economical than others. Also, mind you, all the parts are out of the car!

[BimmerBreaker]

No they can't, the locking ring is in the wrong location.
540 flanges will pop out of the M5 diff if you try to use them.

See post #9 for info.
http://www.bimmerforums.com/forum/showthread.php?1767892-E39-M5-limited-slip-differential-swap-into-an-E39-540i
My apologies, I thought the flanges could be swapped, I knew someone local made them work (can you machine a new groove for the C-clip in the proper location? if so that still may be cheaper than buying driveshaft, etc)

[bimas]

My apologies, I thought the flanges could be swapped, I knew someone local made them work (can you machine a new groove for the C-clip in the proper location? if so that still may be cheaper than buying driveshaft, etc)
No worries. After hours of searching, I got my answers. And, of course, thanks to you guys.

The drive shaft still needs to be swapped, as it's shorter.

I found all the parts - although, still open to a better deal on a diff - but the E31/32/34/38 flanges. Anyone?