I am building up a 1983 300SD, performance injection pump, intercooling, different turbo etc. I want a highway runner that I can get some mpg out of, like 2000rpm at 70mph instead of 3000 range. What diffs fit back there and what ratios exist, I need to pull the rear axle shafts anyways for boots etc I would like to swap the diff too. I plan on building the car so it has power at lower rpm, my direct injection VW's and smart make me want to...and would like to get better economy out of the benz, it is hard to drive it when all the other cars get two or three time the mpg...

2.24/2.47/2.88 (you have 3.07 now). Only 85 and before diffs work. The 2.88 is in the '85 300d/300sd, the 2.46 is in the gasser W126s, the 2.24 is in the W126 coupe.

You're only looking at a couple mpg increase btw. Also, drive slower, it's not just rpms but air resistance too.

The 224 is I believe only from the euro 500 gassers. The us spec 500s run the 247 diff. If you can find a 224 good chance it is a limited slip.

__________________
[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.

There is a EURO 500SEC at our PNP, checked out the Diff, and it is 2:24.
and as of yesterday still had the Euro bumpers and white lights in the front bumper.

Charlie

__________________
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

Thanks for the info, is the ratio stamped right on the diffs? I am looking at changing were the power band of the engine, and want to lower the highway rpms to suit it thats all, I drive a Smart CDI when I want fuel economy!

The Gear ratio is stamped on the lower left facing the rear.
just scrape off the grease.

Charlie

__________________
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

2.24 on a SD is going to make it sloooow off the line. Its ok with a 2.47 and an '85 torque converter (2400rpm stall speed).....I highly doubt you'll see much more than a 2-3 mpg increase with all that work. My dad's 300SD now has a 2.47....and it gets maybe .5 mpg better than before....but its a lot quieter.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Put some taller wheels on it.

Charlie

__________________
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

Yes taller rear wheels is the way to go cheaply.

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

With a Diff swap, make sure you have the axle shims. Those shims are part of the diff, not the axle, even though they are mounted on the axle.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

91 W124 300D Turbo replaced, Pressure W/G actuator installed. 210K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Those shims are unique to both parts, axle and diff.