have noticed that the engine speed has been increasing before shifting from from 2 to 3 and when it shifts it shifts harder. Been looking looking at the posts and it seems it may be the vacuum regulator but wasn't sure since most of the posts cover the 3 to 4 shift. By adjusting the vaccuum regulator does that affect all shift points or just the 3 to 4? I don't live close to a dealer and was wondering if I can use another type or brand of trans. fluid other than the mercedes synthetic? Appreciate the help