ATF type for 1988 300SEL
 

What trans fluid should I be using?
Dexron III or Mercron? What's the best brand?
Are there any good additives for smoother shifts?

DexronIII w/Mercon will work fine, that's what I have in both the 560 and the 4.5, or you could even go with a synthetic ATF, such as Mobile One ATF. No additives are necessary. Any brand name, and some "not-so" brand name are fine. Just recently there was a post about Wal-Mart brand ATF - actually a name brand in Wally World packaging.

ATF type for 300SEL
 

Thanks Mike,

I appreciate the info, if you don't mind I would like to know what power steering fluid I need, do I get MB power steering fluid? Is there a generic brand? or can I use ATF?

Armind

I use the regular old power steering fluid from Pep Boys, amber in color and works fine. While the manual (on the older cars) may state it's OK to use ATF, the current formulation of Dexron/Mercon may not be compatable with the seals, etc in the steering system. I run the same fluid in both the '73 and the '86 with no problems or leaks.