I've got an 04 GT auto, it shifts perfect just driving around town, but when I'm on the freeway in 4th and give it a little gas, the traction control light comes on for a second and the transmission feels like its slipping, revs increase but no effect in speed, it almost feels like its trying to shift to 3rd and its just not catching, but I'm not giving it nearly enough gas for that to happen. I changed the fluid and filter about 6k miles ago, using Mercon V and a motorcraft filter and it shifted great until the other day when it started doing this, the fluid level is good, doesn't smell or look burnt. I'm wondering if its the snap ring on the overdrive band valve that people talk about, or solenoids, cracked check balls, or if I should bite the bullet and get a rebuild if its the clutches/bands themselves. Feel free to point out anything obvious just in case I'm overlooking something. Thanks!