Narrow LSD center?

[Jace]

I bought an LSD center off US Ebay probably 4 or 5 years ago for my car. the listing was for a 320iS LSD so that's what I thought I got.

I have only now gotten around to actually fitting it but have an issue.

 

The center seems too narrow for the case. The case is from the same car my G245 5spd came from, i believe it was a '80 or '81 320i (Australian market)

 

The open center that I removed from this case before attempting to fit the LSD is about 15mm wider from bearing to bearing, meaning that the inside flanges don't reach in far enough to capture the bearings in the outer races.

 

Number on the center is 4061004165 832812  S25 (I understand S25 to be 25% lockup)

Hoping I can get this center to match with a case as I just put new bearings on it. or get 6-bolt flanges that extend inwards further.

 

Any help would be appreciated!

[Preyupy]

Was this case from a 2002 or E21?  The original 2002 limited slip units were narrower so they could be installed in the case.  They used a different set of outer bearing carriers.  They are still available from BMW  part number 3141204048

[Jace]

2 minutes ago, Preyupy said:

Was this case from a 2002 or E21?  The original 2002 limited slip units were narrower so they could be installed in the case.  They used a different set of outer bearing carriers.  They are still available from BMW  part number 3141204048

 

This case is from the E21 my gearbox came out of. I got the entire driveline of that car.

 

Interesting re: the outer bearing carriers, i'll look into that, thanks mate.

[Mike Self]

Your other option is to find a 320i (E21) case and install your LSD innards into it, where it will fit without any modifications.  Then all you'll need to do is get the aftermarket output flanges to make up for the narrower E21 case and allow you to use your original 2002 axles, or make up axles from 2002 and E21 CV joints.

 

mike

[Jace]

after extensive research I believe I have a 2002 factory option 2-plate LSD center, but need the longer bearing carriers as mentioned above part number 3141204048

 

 

[Tommy]

59 minutes ago, Jace said:

after extensive research I believe I have a 2002 factory option 2-plate LSD center, but need the longer bearing carriers as mentioned above part number 3141204048

 

 

Isn't that number for the driveshaft flange? Bearing cover 33111200682

[Jace]

8 minutes ago, Tommy said:

Isn't that number for the driveshaft flange? Bearing cover 33111200682

According to Realoem, both are listed as 'Drive Flange Output', so dunno ?

[Tommy]

I'm baffled since I see different results!? This is what I find from realoem.   04 Drive flange output MIT SPERRE 2 08/1973 07/1977 33141204048 $113.73     05 Bearing cover   2     33111200682 $158.49

[Jace]

hmm, interesting. money i'd rather not fork out, hopefully i can find a purist with a e21 LSD they'd swap for a factory 2002 LSD so i don't need to fork out for these parts. and whether they'd be 4 or 6 bolt parts, who knows.

[Preyupy]

I'm sorry but my cut and paste skills on my phone are not very good.  The part number is 33 11 1 200 682  THIS ONLY WORKS ON 2002 DIFFERENTIAL CASES!!!  The easy way to tell is the number of bolts holding the bearing carrier to the case.  If there are 4 bolts it is from a 2002, if there are 6 it is from a E21. 

[AceAndrew]

6 hours ago, Preyupy said:

  If there are 4 bolts it is from a 2002, if there are 6 it is from a E21. 

 

Probably the only time I'll ever get to correct Preyupy... so here goes. E21's had the 4-bolt case up to the 09/1979 crossover. 

[Conserv]

10 hours ago, AceAndrew said:

 

Probably the only time I'll ever get to correct Preyupy... so here goes. E21's had the 4-bolt case up to the 09/1979 crossover. 

 

+1

 

The 3.64 LSD currently serving in my ‘76 is an example.  The housing was cast April 26, 1978 (“26478”), the unit was assembled May 1978 (“5” over “8”), and it’s a 3.64 LSD (“11  S  40”).

 

So are we, thus, saying that the early e21 differential housings — provided they have the 4-bolt output covers — are identical to 2002 differential housings?  I realize the output shafts are different.  This ‘78 unit was 1/2” narrower than my ‘76’s original 3.90 open differential, measuring to the outside of the output shafts.

 

Regards,

 

Steve

 

Edited August 3, 2019 by Conserv

[AceAndrew]

6 hours ago, Conserv said:

 

So are we, thus, saying that the early e21 differential housings — provided they have the 4-bolt output covers — are identical to 2002 differential housings?  I realize the output shafts are different.  

 

 

 

Yessir, the 2002 case/housing is identical (save for stamping numbers) to the early (>09/79) E21 housings.  The variables being everything else.  The axles are also left over from the 2002 (again, up to 09/79).

[Jace]

I'm up against a bit of a wall with this now, the bearing carrier flanges to suit are over AU$400. 

If I end up going that route, i will take some photos for posterity.

[Preyupy]

"hangs head in shame"  I am so used to the later E21 diffs (because that is where all of the 3.90LSD diffs have been coming from for years) that I completely forgot the early E21 used the 4 bolt cases.  I'll go hide in a cave for a while now.