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BMW differential
Zoophoria - 8/6/04 at 08:42 PM

A colleague of mine has a BMW differential laying that I can get for free or buy cheap, is there any way that I can find out if it has an lsd by numbers or codes on the differential?


Mark Allanson - 8/6/04 at 08:48 PM

I haven't a clue about the numbers for checking for the LSD, but just turn one of the drive flanges - if the opposite one turns the same direction it is LSD, if it turns the opposite it is conventional


Tom Bartlett - 9/6/04 at 12:41 AM

This information was posted on the BMW2002FAQ board:
"Limited Slips and Gear Ratios
The gear ratio is stamped on the driver side of these diffs on the flat area in front of
the side cover. It will show the number of teeth on the gears. For example: 11 40 is
11 on the pinion and 40 on the ring gear for a ratio of 3.64 to 1. If there is also a S
stamped there the diff is a limited slip. Often the S is also painted on as well.
The 2002 was available with a limited slip diff but very few were sold with them. So
it’s not likely that you’ll find one. If you do it may be marked “S 40” meaning 40%
lockup. E21 320I’s that were sold with the S (sport) package have limited slip diffs.
All E21 limited slips are 25% lockup. Cars with 4 speeds had the 3.64 to 1 ratio"

Since I'm rebuilding a '76 2002 at the same time I'm building a Toyota 3TC based Locost (I know, I know, my shop is completely filled), every time I see that neat rear suspension package I get to wondering. Keep us informed.
Tom


Zoophoria - 9/7/04 at 08:57 PM

I did get a bmw differential from a customer at work, it was in quite a bad shape, but it seems to be one with an lsd cause when I turn one of the drive flanges the other one turns the same way. It also has a electric coupling in the rear, anyone knows what that is for?
Could it be for a control lamp that indicates that the lsd is in use? This differential is from a bmw 525 I belive, do you guys think it would work in bec? It feels quite heavy though.


zetec - 10/7/04 at 03:34 AM

Electronic connection could be a speedo sensor.


theconrodkid - 10/7/04 at 04:39 AM

tis indeed speed sensor


TPAFKAMH - 10/7/04 at 04:45 PM

Certainly is a speedo sensor....

Not that I know about BMW things yet...


Zoophoria - 11/7/04 at 09:07 PM

of course!.. why didn't I think of that..heh.. well anyway, do you guys think it could be suitable for a bec middy?