TRANNY TEMP INSTALLATION

[AC Bingel]

I ordered a Isspro tranny temp gauge. It comes with 1/8" thread and adapters to fit 1/4, 3/8 and 1/2 inch. Does any one know if the sensor will fit in the place of the drain plug on the pan or the pressure test port. I have read old posts suggesting these areas but have not found anyone that has actually tried either of these locations. Any response is greatly appreciated.

[bobt]

Hi. I used the pressure test port for awhile on my '93 4L80E and it seemed to work. My gauge came from Banks, but it is an Isspro gauge. That port is where Banks told me to install it. An Astro transmission technician later told me that wasn't the best place to check temp so I installed two pickups on the lines in and out of the trans and use a switch to check between the two. I generally monitor the exit temp because when the torque converter is not locked, this is the temp that climbs quickly.
Bob

[Fredeberle]

BoB T,
Have you noticed any great difference between the temps in the port and the line ?
Fred

[bobt]

Fred, It's been awhile since I changed over but as I recall there was not too much difference between the port and my return line. I think the normal cruising port temp registered about 10 degrees higher than I see on the return line. My return line rarely goes above 170 degrees unless it is an extremely hard long pull. The port temp went up a little higher sooner. As an additional observation, when the torque converter is unlocked on a long uphill pull, I can see outgoing tranny fluid temp at 240+; however, the returning fluid is only at 170 degrees or so.
Bob

[TurboDiverArt]

Besides, when you put it in the line you can bypass the "heater" in the radiator and only use the trans cooler. On mine, my trans temp out of the trans into the radiator is always at least 10-20 degrees cooler than the engine temp. This tells me that the radiator cooler really isn't doing much at all. Might even be heating the trans fluid for all I know.

Art.

[LanduytG]

Best place to put it is in the line going to the cooler. This is the temp you need to watch. If you only have it in the pan or return line and if you let it get to 240* there you have already cooked the trans.

Do not bypass the Rad cooler. When the torque converter unlocks the fluid will get hot real quick and it will be hard to recover from it. I know this by trying it several times. Yes it will heat the fluid if the fluid is colder than the rad, but it will also pull heat out of the fluid if the fluid is otter than the rad.

When you have temp sensors in these places you can play around and see for your self what happen.

Use a quality synthetic trans fluid like Mobile ATF or Amsoil Universal ATF. This will decrease trans temp by 30-50 degrees. Heat kills a trans quicker than any thing else.

Greg