My 2013 cooper countryman s all 4 has developed an issue with the automatic transmission, if I'm driving and have to accelerate uphill most times it will drop 1 gear like from 6th to 5th but sometimes it will attempt to go down 2 gears and instead seemingly into neutral. It's not like a slip, it's like there is nothing there, the engine just revs up and if you let off the throttle it goes back to normal. Ive just been driving the car in manual mode because it doesn't act up at all upshifting or downshifting, believe me I've tried to get it to act up and it just won't in manual mode. Ive also learned that it won't act up when going up through the gears no matter how big the hill or how aggressively the car is driven it won't miss a beat unless it tries to downshift in auto mode. And like I said it doesn't act up every time just occasionally. I'd think if the trans were actually slipping it would do it in auto or manual mode.

I'm waiting on my scanner to come back from being repaired to check for codes in the meantime I did verify the fluid is full and there are no angry sounds coming from the transmission. The valve body recieved a full rebuild 2 years and about 30k ago. The fluid was changed at the same time but could probably use changing again. I'm at a loss because it seems more like an electrical problem more than a mechanical problem I hope some of you folks can guide me on this one! Thanks.

Edit* car has 139k miles on it currently.