I've been running a TCI Street Fighter torque convertor (10" w/ a 12" lock up assembly) for several thousand miles and just recently it seems that the lock up clutch has stopped working.
I'm 100% sure that the solenoid is engaging after the shift into O.D. as the lock up will hold under coasting conditions and I can release it with the manual switch that I've installed in the circuit.
An e-mail to TCI got a response from their tech support saying that I should drop the pan. If clutch material is present in the fluid then yes it's possible that the clutch has burned out.
Anyone else had a similar experience?
I've read in a recent article that Art Carr will NOT provide a convertor lock up in certain applications (like big blocks) because the clutch is notoriously weak.

 

.