I suppose this belongs in the "others" section. Ok, my grocery getter is a 1993 Cadillac Deville and it has some trans gremlins. Once I drive it for 45 minutes +, my check engine light comes on and then it disengages overdrive. It will still shift flawlessly with no slippage through all the gears including reverse, but the overdrive refuses to re-engage until I shut the car off and let it sit for a couple of minutes; then I get about another 45 minutes of drive time out of it before the cycle repeats itself. WTF? I believe the trans is a 4T60-E model. It is mated to a 4.9 liter FWD V8. What could be wrong?