How do you identify what the differential ratio is?

Thanks,
Jeff

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1984 300SD 300,000 miles--two tank WVO setup
2.88 diff & 500SEL anti-squat rear end

Jack up the rear wheels. Turn the driveshaft counting the number of turns it takes to turn BOTH rear wheels one turn. The number of driveshaft turns is your rear gear ratio.

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2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

Annoy a Liberal, Read the Constitution

It is also stamped on the flange of the diff where the rear cover bolts on. Or if you have an open diff you can turn one wheel one turn and count the turns of the driveshaft and multiply by two (leaving the other wheel on the ground).

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[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.

Can`t get much better than this, check these pictures.

2.88 Diff: Use it, or sell it???


Withe the cover off, the number is also stamped on the flat edge of the ring gear.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

charlie i live in SF but i am from SC so i could pick it up in soquel. i just don't have time to repeatedly go to the yards since i have a baby (ten months old). anyway...

I was just gonna say that!

The change in the diff for me wasn't so much in the MPGs or in the noise, its in where it moves the power band. I drive to work on the freeway every day. with the 2.88 I'm better able to deal with traffic at 65-75 mph. Instead of the engine running at the upper edge of the power band at these speeds, its in the middle. I have just a bit more acceleration at highway speeds. It makes the car every nice highway car.

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I personally have not driven anything with the 3.07 diff, but it's safe to say that the 2.88 will certainly make less road noise. As everyone else has said, fuel economy won't be all that different, but you might notice a small increase in MPG. I'd say let it be unless it's really bothering you.

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Never be ashamed to ask for help.

1985 300D
1987 300SDL
1970 Jaguar E-Type OTS
2002 Dodge Intrepid (Traded In)
2011 Ford Crown Victoria

I do have a couple on the shelf. PM me if interested.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Spent some time tonight removing an axle from my '85 Federal TD and it is a 2.88 diff. Out of curiosity, I had a look under my '85 Euro TD with ABS and it has a 3.07 Diff. I had planned to swap the diffs over as I switch cars so that I can keep the ABS....hmmmmm...

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1985 Euro 300TD Turbo

An 84 with 3.47 would be a euro NA. I would not change the gearing to 2.88.

FWIW I am turning something like 1600rpm @ 65 in the '87.

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1995 E420 Schwarz
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#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42