As I stated in 1st gear, I purchased a 08 Model S with auto trans issues. Big slip between 3rd and 4th gear. If you are on the gas hard it wont shift into 4th.
If you baby it, it will shift through to 4th gear.
All other gears seem to shift ok for now. I was thinking of trying a trans service with filter to see if it helps. If not, i know a replacement in in the cards.
If anyone has any advise on this issue, I would appreciate the comments.

 

with more than 50k miles, ATF service is recommended. go ahead and do that service. it should be straight forward. the only two hard parts are getting the pan screw on top of the sub-frame. Personally, I would remove the transmission mount under the fuse/dme box, and jack the trany enough to teach the screw. you would have to use a T30 bit or allen wrench. then the other hard one is the T55 fill plug screw.


here are some more info:

https://www.newtis.info/tisv2/a/en/r...l-sump/HjTwpQu

https://www.newtis.info/tisv2/a/en/r...l-sump/4JnYJ1n

also where are you located?