anyone know the best piace for trans temp gauge sending unit?before cooler,after cooler,or in the pan--thanks

 

Always install the sending unit in the return line. This will give the most accurate temp. reading. To find out which one is your return line, just stop by your local tranny shop and they should have a chart on all applications as to wheather it is the front or the rear line. Make sure you have your tranny code, it is located on the door jamb sticker on the driver's side.

 

There is also a test port on the trans near the shifter which you can put a 1/8" threaded sender into. This is near whre the pcm read the temp from. LOL

 

How is 'most accurate temp' defined?
The hottest temps are right out of the trans converter in the line to the radiator.
The pan temp can only be cooled to a min low temp and not just keep lowering it endlessly.
Putting a sensor in the side of the case is also sensing the case temp and before the converter and not always representive of the fluid temp over time.
Trans operating temp should be of concern in relation to max. fluid breakdown temps.
Monitoring in the pan is after the fact as is the return line and up front locations.
Where is the best location to monitor real time 'max' operating temps.?

 

I put it on the output of the tranny on the way to the cooler. You want to know the hottest point possible.

Adrianspeeder

 

Thanks adrian.
I wanted some one else to say it first for a change.
Guess were going to run Williams Grove this summer.

 

i agree

 

Hook up both, before and after cooler and use a flip switch to toggle between the two It's always good to know how well and if the cooler is working, but if it were just one...yeah out of the tranny before the cooler.

 

Another vote for the trans output line, before any cooler. I installed mine up front in the rubber hose part of the line just before it goes into the rad (the top line) using a brass T I got from Home Depot.

Works great! Tells me the highest temp the fluid is getting. That's what I want to know. If I only see 180* and I know that's before it sees any cooler, then whatever goes back to the pan is going to be cooler anyway.

One nice thing about seeing the temp on the output line is that you know almost instantly when your TC is unlocked. This is a godd thing to know, especially if you are towing something (see my pic below). The most my temp has gotten was 210* while pulling a 6% grade in 90* weather. I was in second gear, but the TC was UNLOCKED... I pressed the gas pedal a little bit harder, and I felt the TC LOCK and the temp started to go down because the TC generates a ton of heat when it's unlocked.... Anyway, it settled in at around 195* for the rest of the pull and then on the down hill side, I let it go into OD and still had to give it gas to maintain speed, so the temp when back to 180* where I'm comfortable with it being at...

Oh, my aftermarket WATER temp gauge hit 210* on that uphill climb, but settled to 195* on the downside and while cruising on the flats.....

Mitch

 

O.K., I think that we are all for the most part right. But I thought that I might check with the experts at B&M. Here is what I am told, "We recomend using the oil return line so as to monitor the true transmission temperature going in, as well as oil cooler efficiency". I believe that it is worded similar to this in the installation instructions with their tranny temp guage, p\n 80212. The ideas that you all have are excellent and have me thinking that there is probably more than one right answer. It would be interesting to do a more scientific study on this one.

 

Call this what you may.
My attempt to find out what the trans life vs temp are, results in all kinds of tables that never say "where" or how the temps were measured.
My testing as a result was done with an infrared meter at various point in the circuit.
At the outlet, the temps are the greatest due to the converter fluid shearing action.
The outlet from the last cooler in the circuit is lower than the pan temp by some 20 degrees.
This indicarts that the pan cannot be cooled below a certain point due to the heat gain directly from the working transmission.
The only practical way to reduce the pan temp further is by replacing the pan with a larger capaciity and of alum construction.
Monitoring at the outlet shows near instant heat rise and drop as the trans is working that you won't see in the pan and less so in the return.
So much for B&M.