2007 Jeep Commander/53K miles/6cyl
About a year ago, I started noticing very small kicks in the automatic shifting in my Commander. Asked the dealer and they could not replicate. About 4 months ago I noticed it had become really hard. It happens the most when the automatic is hovering around 40mph. Within 10mph of 40 either way, it kicks hard and often, much like a studder. Not just when it's shifting. Took it back to the dealership (A true Jeep dealership). They stated my Jeep failed the diagnostic and it needed a tune up and fuel induction service. They did both. Did not work. Then they flashed the PCM. Still did not work. Then it was time to take apart the transmission. They did so, found that the overdrive was burnt out. Yay! We found the problem........SIKE. They rebuilt it and it still does the exact same thing. I have not taken it back yet, but I need some serious education on the possibilities of what it could be. Even with my warranty, the dealership ate my lunch on maintentance services.
Side note: We did notice that when we use manual shifting or there is a full tank of gas, it's not AS bad. But once it gets to about half a tank, it starts kicking HARD.
Any ideas??? PLEASE HELP!