My wife drives a 97 T-bird LX with the 4.6L engine. Recently it has started to shudder really badly at low speeds (25-35 mph) under load, like going up a hill. This isn't the mild shudder you get when it's time to change the trans fluid, but a rather violent bainging, as if the converter is locking and unlocking rapidly. The engine backfires a bit through the intake also while this is going on. Any ideas?? If this is the converter, is there any way to disable the lock-up feature? Thanks for any help!