You guys are great, lets see what you come up for this question.

I just put in my tranny temp sending unit in the test ports on the passenger side closest to the engine. So I have two questions

1) My temp is around 170 to 190 degress. Is this too high? This is driving no load or load.

2) Since the trans fluid and the radiator fluid go through a heat exchanger on the turbo side of the engine, won't that make the tranny fluid the same temp as the rad fluid

If you can answer those questions I would be very grateful

Larry

 

Your right, the trans cooler is inside the engine rad, trans will at least be at engine temp.

An external cooler out in front or somewhere that gets good airflow would be a good upgrade. Some coolers are self regulating so to speak.

Here is a link to PDf article http://www.dana.com/Automotive_Syste...04_Website.pdf

Fozzy

 

i have mine in the test port and under your normal circumstances i see 160 all day long which is probably right at 180 real hot line out temp. jiMMy

 

dodge trannys are designed to maximize at 180 degrees any thing close is good.

 

the warm fluid coming off my tranny is almost always 180 inless ive been sitting in traffic or alot of stop and go then it will creep up... (not in the pan, going to the coolers) with the sensor in the pan you got to wonder what the actual temp is coming off the tranny...

yes it does, heats the atf when its cold and cools when its warmed up.

on a side note there is nothing in your radiator the heat exchanger is on the engine, and these trucks have a cooler above the condenser in front of the radiator.

 

So what would be considered too hot in this test port?
I have mine in the Mag DDpan and it usually stays around 150 but have seen 180 in traffic.

 

I don't know about the test port readings but it is my understanding that the hottest location for a temp sensor is the outlet line from the TC to the primary cooler on the passenger side of the block.
If you look on the dipstick it recommends checking your fluid "at normal operating temperature" or 180*F.
The 1st Gens run hotter than later trannies because we don't have lockup, so, it's all fluid coupling and that runs hotter.
Your operating temps in the crossover line should run between 165 and 185*f with a max high of about 235*F. At that point your breaking down the oils additive packages and loosing it's ability to deal with friction etc...
The '518 trans also has a high limit switch that is set at ....wait for it......275*F
.....you gotta be kidding me....at that point it's pretty much cooked and if you REAL lucky you can save SOME life by doing an immediate service...what were they thinking ???....

pb....

edit: I also seem to remember something from a post on using the test port... if I recall correctly there is some risk there because th sensor can/could contact some internal part(s) and cause damage...but you'd need to confirm this with a specialist in these things...

 

Bushy i heard same thing, mines in the outlet line before the heat exchanger, thats the most acurate reading.