Disconnecting Transmission cooler on Eaton 18spd

This will again vary by the conditions and application. Your findings of running cooler than the engine are typical. You are correct is it doing more heating and is designed more to maintain the fluid temperature. Only if the trans becomes hotter that engine coolant temp will it be actually cooling the trans.

 

This is mostly because the cooler is mounted in the “cold” side tank.

 

If a transmission is running a true synthetic oil ( non petroleum ) would the high temperature threshold not be higher? Also as they do not thicken like petroleum oils at colder temperatures they should not need to be heated?
This is sharing my understanding. Synthetic oil was first developed by Germany while fighting the Soviet Union. The war machines would operate in the cold. Amsoil was developed by an ex aircraft pilot. That was the oil jets used that would stand up to the high temperatures.
Thanks for the education Goodysnap. Being in the sunny south I thank I will keep my preference for no cooler or an air to oil cooler.

 

When l eventually fixed mine l just got one from the local dealer. Its an air type. We mounted it off the bottom of the bunk to keep it in cleaner air. I'd seen a few that were mounted low and were packed solid from road debris. Its been on it for a few years now with no issues.

 

Just take that cooler off. Join the oil lines together so it goes in a loop and block off the coolant lines.

You really dont need a cooler at all on these transmissions pulling 80,000 gross. It will be just fine..

 

They ran no coolers on trans for years with no effect.

 

Both my k100E had E models . Pushing 600 hp and pulled tri axles . Grossing 105,000lbs in the mountains with no coolers. No problems. Both 18speeds. In the summer time temps would get up to 220-230 but with good synthetic that's nothing.

 

@special-k do you remember the cost of the air cooler kit?? How has this been working being mounted under the bunk?? Ive been looking at switching mine over from a heat exchanger cooler and am seeing prices from $130+ for just the cooler to $650 for the hole kit. Looking at pictures its just a 3 row cooler with looks like about 1/2” tubes so would one of the auxiliary trans coolers for pickups work??