here's the # on my diff:
115 35 32 08 I'm hoping it's a 2.88 for my whining 85.
Is there a chart on this site or a link?
Mike

not that i know of. Just jack the rear up and put the car in neutral, spin the drive shaft by hand one turn and count how many times your rear tires rotate, that's your number.

The MB# XXX XXX XX XX

On the bottom left corner next to the cover is where the ratio is stamped.

Forced Ind.
I take it that the number is on the pumpkin housing, near the cover, and not on the cover? I'll have another look. What about a link to a chart?

OK< I found the # stamped into the rear of the pumpkin housing, Not a casting #, but I found it with all your help and a search which said it's located at the 8 o'clock position looking at the diff from the back side. the cover plate does not cover this bit of the diff housing on the lower left side. # is 215 322 288. Whew! I'm glad I didn't get hosed by putting trust in a board member I did not know. I guess I"ll give it a good wire brushing and put some paint on it before I install it.

Thanks again.

Actually this is not correct. the drive shaft turns more times per one revolution of the wheel. If it is a 288 that means the rear wheels will turn togeter one time per 2.88 turns of the driveshaft.

Now if you jack up one wheel and just turn one wheel while the other sits on the ground and count the driveshaft's movement you will need to multiply by two to get the correct ratio. Turn the wheel once and count the ds turns and multiply by two.

Tom W

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Um, you were right until you said the multiply by two... everything else is correct.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
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1987 300TD
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