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Torque
12-18-2005, 03:31 PM
Can someone please help me identify the diff in my car. Car is a m20 07/1990 525iA.

Also, how does one tell if one is limited slip or not by looking at it ? I'm looking at a diff on eBay and it has these numbers:

4.10 1211699.9 +GF+ 201104

TIA

Qsilver7
12-18-2005, 04:29 PM
if you go to the online parts database and input data that fits your cars mfg date...the diagram only list a 4,10 diff (you can click the link that says "select another car" and then enter the last 7 digits of your VIN to get a more specific parts diagram): http://www.realoem.com/bmw/showparts.do?model=HC23&mospid=47402&btnr=33_0004&hg=33&fg=05

Bmw diffs that are LSD (limited slip diff) ...they have an <b>S</b> in front of the ratio...it would read S 4,10 on the diff's tag.

Torque
12-18-2005, 04:41 PM
I just looked it up on RealOEM, and the LSD part number ends in 889 and the open diff ends in 887. The number he has listed there ends in 999 ... I emailed asking the seller if it is LSD.

Does anyone know what diff the m20a has tho?

Qsilver7
12-18-2005, 04:48 PM
Does anyone know what diff the m20a has tho?

I'm confused...what do you mean by "what diff the m20a has"? Do you mean is it open or LSD...or do you want to know what the ratio is?

The supplement column (on the parts database) reveals what the ratio is ... and like I posted previously...it is the 4.10 differential in your M20.

If you want to know "what" type ... open or LSD...the LSD diff would have been optional (open diff was standard equip) and there is a metal tag on the BMW diff that will tell you what the diff ratio is and if that diff has limited slip...there will be an S in front. (I thought it was clear in my first post...sorry if it wasn't).

Torque
12-18-2005, 05:04 PM
Sorry, I came off sounding wrong on the question. I know it's a open diff, I wanted to know the ratio.

Thank you

Rigmaster
12-18-2005, 06:07 PM
I just looked it up on RealOEM, and the LSD part number ends in 889 and the open diff ends in 887. The number he has listed there ends in 999 ... I emailed asking the seller if it is LSD.

Does anyone know what diff the m20a has tho?


The number you listed for the Ebay diff has nothing to do with the part number. The only important number is that first one- "410"- that tells you the ratio is 4.10:1 and since there is no mention of an "S" there- it's NOT an LSD.

So, sounds like the Ebay diff would be exactly what you already have in your car now.

Bret.