Well I have a problem with one of my Mercs. Its a 2002 320CDI with 4 spd auto gearbox and it has problems shifting from D to R. That faults is intermittent. Sometimes after long drive I have some luck to get it shifted. On other hand it drive and shift,downshift gear without any problems. Seems as gearbox works without any faults. I had it scaned once (non-Star scanner) and it didnt bring any faults to gearbox. Once lucky enough to shift it from N to R it goes to P and from P to any other without any problems. Is it entire selector or is it something simple?