A tough one....

[H2 Ranger]

The internal cooler of the radiator serves a dual purpose. It heats up the transmission oil for cold areas such as Alaska and it also keeps the oil from overheating as well. Often the Engine runs hotter than a desirable transmission temp. So routing the transmission cooler thru the radiator in the current setup makes the trans temp go up more than desirable in a arid enviroment. I believe that you will get more life from a Cooler Transmission say about 175 degrees, and the transmission oil will not break down so fast. While I am not an expert on thermo dynamics, I still think a lot of transmissions are destroyed from improper operating temps. While in your case I would think it was a poorly mfrg radiator, but it has given you the opprotunity to try a remote cooler. If you decide to get it done that way make sure you get enough surface area for the cooling and have an end result of what you are looking for. Also hope you wife condition has improved.

[H2 Ranger]

Originally Posted by PhilD

Water in the tranny is bad, it will not run real well and the engine will surge and all sorts of things as the tranny gets worse, and allows for less/more resistance due to the contaminated fluid.

Good point Phil, I would add that the mixing of both oil and water changes the surface tension of the liquids allowing air in the oil. Air is compressable and will haper smooth servo and spool valve operations. Mabee this condition was part of the issue as well.