My transmission has not been enjoying this hot weather here. Recently it started slipping out of 4th gear. Sometimes it goes to 3rd, sometime it goes completely out of gear. I checked the fluid level, and added some fluid. I also added some Trans-X to it a couple days later. Still no luck. Checked the level again and realized I had overfilled it. I drained out enough to get it back to normal, and the fluid was a beautiful red color, no burnt smell, no dark fluid. I changed the fluid and filter about two years ago, and did a drain and fill (no filter change) about 6 months ago when I was diagnosing a "broken" throttle position cable. Turns out the cable was fine, but that piston was stuck. I worked it free and adjusted the cable and everything seemed to be working fine at that point. I thought it might be the B-2 piston, but the symptoms listed on this site don't match up with mine.
Additionally, it was only doing this when the transmission heated up, but now it does it within 5 minutes of driving. I would prefer to do the work myself rather than a shop.
Thanks for any help and opinions.