I changed back to a Dex III equivalent from Dex VI (Pennzoil Dex VI). The tranny shifts better (including in New England winter).

Castrol USA, who sells Dex VI products in the US from which they can earn more money, recommended me their Castrol Domestic Multivehicle (a Dex III - H equivalent) for my vehicle: 1992 300D. I asked again whether Dex VI is better than Castrol Domestic Multivehicle saying that I am looking for the "best" for my car, but they recommended Castrol Domestic Multivehicle again.

I also changed from Mobil 1 75W-90 to Valvoline Durablend 80W-140 for my rear differential,
from Shell 5W-40 to Shell 15W-40 for my engine.

My car runs on original tranny, differential (very noisy), and engine. 316700 miles on it.


By the way, while I was looking for ATF for my car, I found an interesting fact. An MB dealer in Somerville, MA, uses Autozone brand Dex III equivalent for old MB's, which is even cheaper than the Dex III equivalent from Castrol, Pennzoil, Mobil, etc.

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1992 300D 2.5 turbo diesel. 319 k miles.
124.128 chassis, 602.962 engine, 722.418 tranny.