Hey y'all, I got a trans temp gauge for my truck ordered now. Where is a good test port on the tranny that I can install the sender in. I dont want to put a T in a line or drill into the pan, so are there any test ports I can install it to? Thanks

 

Test ports don't always have fluid flowing past them. There are 'adapters' that clamp onto the line, they read a bit low, but, don't have to cut anything.

 

I've seen quite a few people adding trans temp gauges to their trucks and was looking at doing the same to my 99 2500 5.9 in the future to keep an eye on it, but I was playing around with my scanner, it's an Injectronic CJ4 with the Chrysler addition pack, and I noticed a trans temp reading while watching the live data. On the list of data I also have a number of diesel only readings like the boost pressure, wastegate pressure, etc, but since I've got the 5.9 gas in my 2500 these readings just hold constant so I figured it shares a wiring harness to some extent with the Cummins. The trans temp however does appear to read somewhat correctly. This morning the sensor read 13 degrees(55 degrees Fahrenheit) and after half an hour on the interstate 64 degrees(147 degrees Fahrenheit). The temp outside this morning was about 45 degrees F so it was reading slightly low. Also the operating temp might also be low, but I think the PO bypassed the radiator cooler in favor of an aftermarket so I need to look closer at that.

Just wondered if anyone else had seen or heard of a factory temp sending unit on these trucks.

 

Is there a test port on the 46RE that does so I can use it?

 

Simple answer - no. To be of any value, it needs a constant flow of fluid. Any of the test ports are pressure, and when pressurized, ther is no flow. Best to cut line and install a T or install a deep Derale pan (or other brand) with a temp port in the pan.

 

Putting it in the line will give the most accurate reading as stated.

http://dieselmanor.com/dm_products/FTG-MFD.asp

 

On the 96 and newer transmission, the temp sensor is integrated into the governor pressure sensor. On the older trannies, it was an actual sensor on the trans cooler line. (if you had it at all.)

 

HeyYou,

thanks for the information about the sending unit. I did notice readings for the governor pressure as well. I checked my tranny cooler setup and it appears I have a factory tranny cooler which is also routed through the radiator cooler and the check valve has been removed.

I wonder if there ever was a factory tranny temp gauge, perhaps on the diesels, that would just be a plug and and go. Of course then one would have to be confident in the reading of that sender, which at only ~150F hot mine seems to be running pretty cool.

 

No stock trans temp gauge that I am aware of. Lots of options for installing an aftermarket unit though. The PCM knows what the trans temp is on the 96 and newer ones, trying to extract that information and display it though, that's another challenge entirely. ScanGauge supposedly can do it, but, I am not 100% sure that it is a supported feature on the dodges.