I have a 99 TJ with a 2.5L and 3 Speed Automatic. 30rh I believe. When going down the road and the converter is in lockup the jeep will jerk at 45mph on any kind of incline. Never at 40 and never at 50 but always at 45mph. It's driven me nuts to the point that i mounted a switch inside that I can hit to turn off the lockup solenoid. If I get on the gas and keep it from shifting into lockup until past 45mph it's fine until I slow to 45mph. It seems my problem would go away if I could install something that would automatically keep it from going in to lockup at less than 50mph. Is there anything that will accomplish that? My wife drives it more than I'd like and I don't like leaving the solenoid bypassed all the time as I'm worried about the transmission heating up. Any help much appreciated.