My 2000 lesabre (116,000 miles)expirienced some transmission problems. The shop I took it to replaced the valve in the valvebody, TCC solenoid, and the brake light switch. They explained to me that I should take it to a dealer to have have the electrical problem with the brake light switch investigated since they think that this might have been the root casue of the problem. They also said my computer must be reprogramed by the dealer. I scheduled an appiontmnet with the dealer but the first opening is not til next week. I would apprecaite any insight anyone has to this problem.

 

This is someting I just thought of off the top of my head. When you are driving along and the car is in overdrive the torque converter locks up. Anytime you tap the brakes the torque converter unlocks. I am wondering if you are having a problem with the circuit that controls the brake lights. Maybe a short and the car thinks you have put on the brakes and unlocks the torque converter.