Was driving about 60 mph for about 1 hour with my 1992 Chrysler Lebaron Convertible when it was necessary to decelerate and begin to apply the brake. At that instance, the automatic transmission shifted into low gear. The shift lever remained in the Drive position. Pulled off the road, shut off engine, restarted, placed shift lever in drive, no change, transmission stayed in low. Stopped again, shut off engine and turned the key on and off three time and started the engine again. Placed lever in drive, still stayed in low gear. Being 80 miles from home, had the car trailered to my Chrysler dealer. Being a Sunday, the mechanic drove the car on Monday and it shifted as it should. 300 miles of driving since has resulted in no repeat of the problem. Any ideas as to the cause?
It was probably in second gear, not first. That’s the “limp mode” for that transmission. One of the conditions that will trigger limp mode is overheated transmission fluid, which is what I think happened here. First thing I would do is ask your mechanic to drain the transmission, change the filter, and then refill with genuine Chrysler ATF +4, not some BG universal fluid that claims to be compatible. The next step will be figuring out why it overheated. If you haven’t had it done in the past five years, you’ll want to ask your mechanic to drain and refill with fresh coolant.