My understanding it that Mercedes originally said 10w oil but now will tell you to put any dextron in it (yes, ATF).

Has anyone trie MTF or anything else?

.

IMHO any quality 75w80 is ok.

.

__________________
w126 500SEC gen II euro, powered by OM617 turbo stolen from 84 300SD 2.88 diff,EGR blinded
next wish/project: w114 coupe OM603 powered

YOU USE 75W80 IN YOUR MANUAL GEAR BOX?!?!

Wow! They make good coffee in Pennsylvania, I guess.

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."

Thats a HUGE difference from ATF. I didn't think that would work at all. How does it shift?

1980
240D
Four speed manual transmission.
Dexron/Mercon III (ATF).

I flushed out the previous thick sludge, three times before it shifted correctly..

In sub-zero temperatures, the previous (guessing) 80/90 gear oil prevented shifting, and/or gummed up the synchromesh = grinding in all gears.


.

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1985 300SD
1983 300D
2003 Volvo V70

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I'm thinking of going with Red Line D4 ATF in mine (82 240D 4 speed), but haven't decided for certain yet. I'm not going to be changing it for a couple weeks, waiting until it will at least be above 40 outside.

I used Mobile 1 Synthetic ATF and works fine. MUST smoother. I ran some cheapo stuff to flush it out (Autozone). Drained, and put the good stuff in. I think the Haynes manual indicates AFT, also.

I just refilled mine with Penzoil "Syncromesh". I have been satified with Dextron, but this is a newly designed oil for these constant mesh transmissios. I have heard good things about, so I am using it.

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Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!

DO NOT use 75W80. use ATF or 5W20

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1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

You can use a MB 235.1 approved 80W gear oil, but ATF was prescribed.

This is incorrect. 80 weight oil is fine for the axles, and the differential, but the manual gearbox needs a thinner oil or the syncros will not function.
5w20 should work, straight 10w, any quality ATF or preferably a synthetic ATF...

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

80W gear oil is as thin as ATF.

Oil weights aren't absolute numbers.

...

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Um, I'd need you to show me some documentation for this... weights of oils are a standard of viscosity universal across all brands and types of oil... oils with the W in them between two numbers, are manufacturers multi-viscosity oils, and can vary from temp to pressure and useage...

ATF is in the 10W range...

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!