dridley

The size of the Hex is 4mm. Use a regular Allen key, the 'L' shaped old fashioned one with a small cheater (like boxed end wrench) for more leverage. This is from my experience on the 2006 C230 w203. Now to figure out which fluid to use. I've got the Shell Transmission Fluid. Should work. A little questionable on the semi synthetic part though thought it would be a full synthetic. Sealed for life ya know!