My 545 sometimes seems to get between gears when rolling to a stop but not stopping. The engine revs up and the tranny shifts in and the the rear feels like it is going to be pulled out.
Does anyone have info on auto tranny problems?

 

Dealer time my friend. Get a proper diagnosis. I have not heard of your exact problem before--as I read you. Some experience what is called "tranny slam," but TS does not seem to be what you are experiencing--except maybe for the "going to be pulled out" comment. TS occurs, AFAIK, only upon acceleration from a slow speed. Then, the tranny "catches" with such force that one feels a good jolt. TS does involve a loose, between gears feeling before the slam occurs. Maybe you do have TS.

 

There were also software fixes for reported downshift problems, loss of power, loss of steering function associated with downshift. These were back a way's in time so if u have older 545 that has not been updated then do indeed do as Znod recommended.

The sense that it is not quite sure where it is effects me only on the last downshift in either D or DS (or D "Sport") as I roll to a stop - usually just before braking. Does not do this in the 6/5, 5/4, 4/3 in D or 5/4 4/3 in DS. But that very last downshift when slowly rolling is like it falls in between gears, RPM drops below normal shift point ~ 800 RPM on that last shift before complete stop. I am used to it and believe that if I hit accelerator hard at that "in between" point I could cause the so called Tranny Slam, so I don't. One reason I use alot of Manual STEP shifting is to control all this.

 

Do a search on: Steptronic slam or: transmission slam or just plain: slam

I suspect that is what you are describing. It was supposedly fixed by a software update, but some of us still experience the problem occasionally. I have not had a slam for quite a while.