Mike, to 12Vs point, a manual torque converter lockup switch is a great addition to your truck to improve efficiency and reduce trans temperatures.
If you've driven any newer trucks, especially towed with them, you realize that the 4 speed auto is basically the Achilles heel of the 3rd gen Cummins trucks.
Before the ram Mafia jumps in, yes, it's a very simple and fairly reliable transmission, but due to only having 4 gears, you have to drive around the trans sometimes when towing.
Either way, deep finned pan and mystery switch are the 2 best easy basic mods you can do to a 48re for towing.
