[sturdei]

No answer but mine is doing the same thing. It started happening shortly after the 150,000 mile transmission fluid change. I've tried additives to teh transmission fluid but nothing helps. It will run for just a few miles in overdrive, then drops back to third gear and won't go back into overdrive again until I shut it off and start the engine back up again. I can't help but think it's computer related because of that. Also when in overdrive but running in third gear, when I let off the throttle to slow down, it comes out of gear and the engine idles, regardless of my driving speed at the time. Then when I hit the gas again, it revs up and shifts back into third gear and continues on its way.