4L80E Temperature

[Spindrift]

It may be time for a transmission temperature gauge.

What temperature differential can I expect between a sending unit that is located in the transmission line vs. one that is located in the tranny pan?

Thanks.

[rjwest]

I put mine in the line going to top of radiator.
I figured it would be hottest oil, did't want to
mess with pan....

I use as referance... Normal 150-170
Hot day at speed ,TCC locked, 200, Long hill climb
TCC unlocked 250 deg and rising( not good).

[bobt]

Hi. I have sending units in both lines as they exit and enter the transmission. I use a switch to go between each sending unit to read each with the one gauge. I normally keep it on the output line as this is the one that runs warmer. Normal operation is 150 to 170. If on hard pull may get close to 180+. If torque converter not locked up, then temps out of trans can climb rather quickly; however, even when the unlock temps out of the trans get up to 240 or more, if I check what is coming back into the trans, the temps are down around 170-180, so it appears that the high temps coming out of the torque converter are fleeting and immediately cool off. When carrying my 4000# camper and towing a Jeep Wrangler with torque converter unlocked on hills, I have not seen trans fluid temps on the return line over about 190.
Bob

[Spindrift]

Thanks, Bob. Are you using dino oil or synthetic ATF in your tranny?

[bobt]

Spindrift
Dino everywhere.
Bob