Ok so I am new here and this is.my girlfriends car and I do.know things about cars I've. built a few race engines. This is the 4 speed auto hooked up too the V6. So what is going on is the transfer from second to third is reving about 500 rpms and then slamming the gear sometimes it shifts smooth sometimes it slams it. So the fluid is good n full and not burnt the car has 143k on it. I took it to a shop to have it scanned they said it didn't pull any codes after I watch them write the numbers down and look them up on the computer right in front of me. They test drove the car and they said the clutch was slipping. So im working on second opinions and its going to different shop on friday. I was thinking it was possibly the shift solenoid for that gear. It also down shifts fine and all the shifting through the other gears is perfectly fine. Thanks for. any help I was quoted 2500 for a rebuild