Do you put it in neutral before backing out to load the converter?? Does it rev everytime you put it in reverse, or just when its cold?? I always warm the trans in neutral before I set out, even in my daily 03 Ram! Not going to solve your high speed limit, but may be a false reading on the reverse issue! My truck revs way up in reverse if I don't load up the converter first, and it has a 3:91 rear!!! Just throwing out ideas!!!