RE: Controlling torque converter lockup
Go with the chip from Dennis. If you're experiencing shudder, this is what a knowledgable person had to say about it...
There is one more problem that I have not mentioned and it affects mainly the 11.25" converters. The lockup plate is about 10" in diamter. The one in almost all Marks, until mid '97, is totally flat. As it pushes back and forth and applies, it deflects. There is fluid pressure pushing from the back side of the converter toward the front. After alot of cycles it permanently deflects and is now shaped like a contact lens. When this happens the radius at which it contacts the front of the converter is reduces. Since the torque capacity of the clutch is directly proportional to the radius it applies at, the smaller the radius the less capacity, the more prone to shudder.
In mid 1997 they changed the lockup plate to be similar to the one in the 12" converter (this was changed in 10/94) to have ribs in the plate and a thicker plate itself. This prevents the deflection and keeps the contact radius uniform
So, put in a newer converter and you'll be OK.