I have a 1997 E300D which I have a slight slipping at various times. It has 238,000 and Im not sure if the tranny fluid has ever been changed so Im going to change filter and add new fluid. I read somewhere that the modulator on the tranny can be adjusted to "tighten" up the tranny and its bands a bit. I however amm unsure what to do exactly. I would appreciate any help. Thanks