I have had my trans temp in for about 3 days. here is my problem. When I am cruising around town my temp sits at about 120-140. When I am on the highway cruising at about 65 it will go below 100deg. But when i get to slower traffic it goes right back up to 120-140. Temp around here has been average of 50's and i have the sensor on the HOT line of the trans cooler with the massdiesel trans cooler line. Could it be that the sensor is not in the flow of oil with the massdiesel set up. The sensor sits about .75" away from the flow of oil. When I spoke with scott there he said this isnt a problem. Any ideas why my trans temp is falling below 100 cruising on the highway?? Or is this suppose to happen?

 

Sounds normal to me, I have the same setup.

 

When not in stop and go traffic the trans torque converter is in "Lock-Up" which generates VERY little heat.

Sounds perfectly normal.