So have this 81 240d, what year range can I look at for different gear ratios that are "bolt in"

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Brad

Bunch of old metal, trying to keep it on the road....

R/C 107 - '73-'85 all w/ 6 cyl engines
W114/115 - all
W116 - all w/ 5 & 6 cyl engines
W123 - all
W126 - '81-'85 all w/ 5 & 6 cyl engines

Supposedly ANY 1985 and older diff from a W116, W123 and W126 will fit.

Gen 2 W126 diff will NOT fit.

Sourced from here.
https://mbturbo.com/gear-ratios/

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1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.

V8 diffs wont fit directly as the yoke is bigger and needs to be swapped over. Also the washer behind.

larger rear tires will help fuel mileage

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

Whilst the some of the specified differentials will fit in terms of "fill the hole" not all of them are going to be especially fantastic when used in a 240D

The final drive ratio is important - especially if you have an automatic transmission and if you wish to have an accurate speedometer reading.

Speedometer gearing is matched to final drive ratio - shifting points more or less "matched" to expected final drive ratio.

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

If you tell us your objective we can advise on ratio decisions for your needs.

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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.

Awesome thank you!!

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Brad

Bunch of old metal, trying to keep it on the road....

Have this 81 240d 4spd, but has a 300TD swap, has the 3.69 rear now going for the 2.88 for better highway speed and possible mileage

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Brad

Bunch of old metal, trying to keep it on the road....

Also, will a VIN tell me the rear ratio if I xA t get to it to physically see it

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Brad

Bunch of old metal, trying to keep it on the road....

VIN



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Brad

Bunch of old metal, trying to keep it on the road....

The serial number will tell you what it left the factory with. Look on the flat part of the diff where the rear cover bolts on and it is stamped there. You're on the right track with the 288. Unless you live in san fransisco then I go a bit lower.

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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.

Yup knew about the stamp just can't get to it where it is sitting ill see if I can find a VIN decoder to tell me..

Thank you!

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Brad

Bunch of old metal, trying to keep it on the road....

Well found a few decoders but nothing on the VIN tells the rear ratio...so I guess it will be that I have to have some help getting this thing up where we can get underneath it to look for the stamp.....

The VIN says US spec ‘83 300D. I think that means 3.07. 2.88 might be MY ‘85 only.

Sixto
98 E320s sedan and wagon
02 C320 wagon