Thanks Keith for the reply.
I initially ran it with the radiator trans cooler only, and the temperatures were similar. I figured that a large external cooler has better cooling capacity than the radiator cooler. Apparently it doesn't. My next step as far as trying to control temperature is using both coolers, as you suggested.
I am aware of the TV cable. I had to fabricate a bracket for the TV cable as they aren't available anymore, at least not for the diesel engine. The injection pump does have a hookup for the cable. There are diagrams available that show the correct geometry of the TV cable hookup, and I followed that closely. I used the wide open throttle method to adjust the cable, which basically means max throttle equals max travel on the TV cable. I have not checked the line pressure, which I should probably do. Where exactly is that pressure reading being taken? Also, can you give me the procedure on how to do it?
You say the only difference between 3rd and 4th gear is the 2/4 band being applied. Isn't there another major difference? In 3rd gear the ratio is 1:1, meaning none of the planetary gears are actually being used, while in 4th gear, with a ratio of roughly 0.7:1 the drive shaft runs faster then the engine. Could the howling be coming from the planetary gear set? Then why would it be so much worse once the TC lockup is engaged?
Steve