I have owned my stock jeep for a while, but now my sons are getting a bit older and are interested in "trucks and dirt", so I have started doing some stuff to make it more off-road worthy so we can all go out and play together.

I installed a couple of transmission temperature gauges (one for the supply line and one for the return line) so I could see the temperature drop as it went through the factory transmission cooler.

I noticed that it was pretty regularly around the 190 degree mark on the supply line and I had a decent drop of about 20 - 25 degrees on the return line). I replaced the small factory tube and fin cooler with a larger Hayden aftermarket cooler of the plate and fin type that was supposed to be more efficient.

The good thing is now that the transmission is running cooler (rarely hit the 180 degree mark) but the temperature that is showing between the supply line and the return line are almost identical and showing hardly any temp drop.

Anyone else experience anything similar? Any reason for this?

I am not overly concerned about it because it is running much cooler, but it has certainly piqued my curiosity.