I would like to change the diff oil on my 1984 300D, I went to a local parts store to ask what weight of oil it calls for. The first thing I was asked was "do you have limites slip or Not". How can I tell if I have one or not? Also, any recommendation on what to use? I use M 1 on my other vehicles. Thank you.

No W123 chassis came with LSD.
Use a good quality 75W-90 or 80W-90 GL4 or GL5

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MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
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Retired Moderator

When you pull out of the car wash, gun it!! Both wheels spin? 8 ^)

Don't ask how I know.....

imo, the off the shelf m1 gear oil is crap. the good m1 is called "delvac 1" and isn't sold in stores, you have to mail order it. porsche uses mobil delvac 1 as the factory fill in their race cars, and it's also popular for heavy industrial machinery, dump trucks and such. it's a real heavy duty gear oil. the "regular" m1 gear oil in stores is a joke, it isn't even a real synthetic.

mobil delvac 1 is also a mercedes approved gear oil, while the off-the-shelf m1 is not. it's the same story with porsche, where delvac 1 is a porsche approved gear oil, but off-the-shelf m1 is not.
http://www.mobil.com/USA-English/Lubes/PDS/NAXXENCVLMOMobil_Delvac_Synthetic_Gear_Oil_75W-90_80W-140.aspx


i'm using redline 75w90ns in my e300d. redline synthetic fluids are outstanding, and you can get them on amazon with free shipping, and more shops carry redline than delvac.

as for limited slip, no, you don't have it. mercedes has never been a big fan of limited slip differentials, for whatever reason. even on their modern cars, they use electronic gizmos in place of a proper lsd. i don't like it.

For any car/truck to check jack up one wheel, leaving the other side on the ground and try to turn it. If it is a true limited slip or automatic locking rear the wheel will not turn by hand.

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1977 240D turbo

If you want Limited Slip Diff, pull one out of a W116 6.9. It is a 2:65 ratio.

http://www.peachparts.com/shopforum/performance-paddock/242313-116-126-differential-swap-pics.html

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

very nice!! unfortunately, w116 6.9's don't exactly grow on trees.

I have only come across one in the past 4 yrs of hitting the various PNP`s, and that was a yr ago last July.

It`s the hunt, the challenge of junk yarding for the elusive parts.


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