190e Manual Transmission Fluid
 

Hi Folks,

I'm trying to determine the correct manual transmission fluid for a 717.432 5-speed.

I've researched the forums and it is not clear to use

Dexron III ATF or

75W-90 Fully Synthetic Gear Oil or

75W GL-4 Manual Transmission Fluid?

Can anyone recommend the correct one to use? Thank you!

Spec is DexIII ATF. I have very good results using Redline MTL.

I went through this exercise 25 years and 25,000 miles ago for my '88 190E 2.6 special order five-speed. IIRC the Mercedes spec is 20W-20 non-detergent engine oil (try finding that, today) or Type A Suffix A ATF that is the old, original GM ATF spec going back the first Hydramatics in the 1940s that had a small amount of whale oil as a friction modifier to prevent wet clutch chatter.

Of course, whale oil was outlawed in the 1970s, and the current anti-chatter additive is a synthetic product.

After more research I decided to go with Redline MTL, which is the same viscosity range as ATF (70W-75), but is formulated for manual transmissions that are speced for ATF, so it probably doesn't have the friction modifier, which is not necessary for synchromesh transmissions, but I think it's okay to use modern Dexron.

You'll find a similar situation for the rear axle oil. The Mercedes spec is 85W-90 GL-5. I did ascertain that Pennzoil offered this product, but couldn't find it... finally called Pennzoil and they said it's not available in North America, so I used commonly available 80W-90 GL-5.

I was chagrined that Mercedes recommended lubricant products than are either long obsolete or not available in the USA.

Duke

Thank you both for your recommendations and have decided with the RedLine MTL! Much appreciated!

I think if you go through the 231’s and 235’s, you will find that approved manual transmission oils are 75W or 75W-85W gear oils.

https://bevo.mercedes-benz.com/bevolisten/bevo-sheets-sort1.html

It looks like MB has not changed their ways as most of the products on that list are likely not available in the USA or difficult to find if they are sold in the USA.

It's great to know what fluid you need if you are in Timbuktu, but what about the USA.

Commonly available passenger car hypoid axle gear oils in the USA are 80W-90 GL-5 and 75W-90 GL-5 with the latter usually classified as a "synthetic".

Most modern manual transmissions spec ATF (70W-75) or 75W-90 GL-4.

Duke

They will only spec suppliers who applied to have their oils considered, but 75W gear oil is pretty standard stuff. But I see a few American suppliers in 235.1 too