Originally Posted by
twanger
Viscosities mentioned in this post are pretty far apart ?? 0-20 & 75 ? From my 60 some yrs experience w/ transmissions , 75 seems more applicable but then todays lubricants are nothing like yesterdays for basically the same mechanical mechanism .
Sae for motor oil is different than transmission oils.
I read on this forum people use 5w20 motor oil as gearbox oil but thats not for me, i will never use engine oil on a gearbox.
As you can see on this pic, motor oil and gears oil is not the same SAE scale
https://syntheticwarehouse.net/wp-co...ositychart.jpg
For sure, the original oil for this gearboxes used in service operations at MB Dealer is 75w85 GL4, MB235.10
Any other oil is not the best option for this gearbox.
In my case with Febi 75w gl4 mb235.10 (instead 75w85) the smooth is great, and gearbox seems to be perfect