Transmission Fluid for Stick Shift
 

Does anyone know what type of transmission oil a 1983 240D stick shift would take? I asked the local auto parts store and they didn't know.

ATF or Redline MT-90

Mine (1980) has Mobil1 10w-30 as per FSM.

I might try Redline MTL next time....

I have used ATF. The last 2 changes have been Mobil1 10-30. The synchros are still notchy with it .... maybe next time I'll try Redline.

We've had Redline MTL in the 77 240D's 4speed for the past couple years and 10k or so. I'm not sure exactly how long.
I've been so happy with it in my 242T that I flushed then changed the 240D to MTL right after we got it. Nice smooth shifts and a relatively quiet gearbox, considering the age and design.

The manual for my '83 240D calls for ATF. I think there were one or two years where Mercedes called for engine oil. I think that every year from the beginning of time except for those two years or so, Mercedes called for ATF. My ponton calls for ATF. I think that the later manual transmissions, i.e. like my '83, is the same transmission as the earlier ones that called for the engine oil. I don't know whether or not Mercedes changed their recommendation or not on the engine oil for those transmissions.

Redline oil recommends MTL for that transmission. I wrote them myself and asked for my car.

Scott

MT-90 is the wrong oil to use. Since ATF is the fluid to use, D4 ATF is the correct type of RedLine oil.

The folks at the lube place looked it up and it said something like GLS. Any ideas of what that would be?

It's not GLS, it's API-GL5. API GL5 is a heavy duty lubricant used mostly in rear ends and transfer cases though. I don't have a standard transmission, but I've never heard of using ATF in one!:confused:

The folks at the lube place are uninformed. GL-5 is gear lube, AKA 90W. This works well in some manual transmissions, but not Mercedes. Run cherry juice (Dexron III or equivalent) and your transmission will be happy.

Love the quotes by Barry Goldwater, the greatest Senator to ever serve the United States and my favourite along with Ronald Reagan!:D

I have Redline MTL in my manual 240D. I had a little bit of rough shifting that seems to have gone away. But that could have been change because I put new fluid in.

So now I'm a bit confused. Could I just use some heavier high quality manual transmission oil or is there something that Mercedes calls for specifically?

I think we all are....due to the changing instructions from Mercedes over the years. Pick your poison and see how it works. I had more trouble with mine when I had DexIII ATF in it Motor oil works better for me, and next time I'll try the Redline MTF and see which one gives me the smoothest shifts and stick with that.