rear identification

[eurosport22]

so im sure there is an easy way to identify the rear end in my car just as you would with the head and block of a motor. i have a 86 es that i just swapped my s50 and zf trans into and from what i read i have the 2.93 in my car. i want to make sure before i go and get aother one, which i am looking for a 3.2 or even the 3.46 ive heard about. i dont do a ton of highway driving and would really like to wake the car up with the better gear ratio. is there a printing on the case that will tel me without cracking it open. or can someone at least confirm that the 86 325es' came with the 2.93 because that is what all my research has told me

[frankie591]

there should be a metal tag on one of the diff cover bolts. It will say your ratio. Alternatively you could put your transmission in neutral and spin the driveshaft by hand and count the number of turns of the driveshaft vs. the number of turns of the rear wheels.

[evandael]

yeah just grab the input shaft (hehehe) and give it a spin. see how many times the outputs spin. it's likely a 2.93.

[eurosport22]

cool. sounds good thanks guys

[frankie591]

ya 325e's mostly came with 2.93 rear ends, but a lot can change in 25 years :-)

[SmokeE30]

early es could also have 2.79

[eurosport22]

its 11/85 build date. and im the second owner of the car so i know its factory