I had a set of trans lines that come with a motor and trans I bought. Not thinking I threw them away. Now I find out they are not reproduced(at lest to my knowledge). I don't need them but would have kept them if I realized they were not reproduced. You could drill a hole in the existing line and weld on another piece like the factory did. Of course you would have to flush out any chips prior to use. I think getting fittings to fit between the trans and the line would be easier. I would get a gauge pod for the A pillar and put a meter in it. Then you monitor the temp any time.

 

The cooler lines are low pressure, so, even a compression fitting would work just fine.

 

Greetings,
01 1500 w/ tow package
Here is a shot of my setup

I got a toggle switch for 2 sensors...1 for hot before the cooler and one on the return line...I have to find the return line I tapped into...it's not here (perhaps I used the service port on the trans?)

I put the toggle switch on/in the dash bezel ( not ideal...keeps being sporadic with hitting the back)

 

Out of curiosity what kind of temperature differences do you see between the sensor right out of the trans versus the one after the cooler?

 

140-150 on days up to 85deg hwy cools it down more
180-210 summer days on streets hwy cools this down some

towing: 210+ (i think i hit 240deg when i was towing max payload up the camarillo hill on the 101 (its a long climb like cajon pass on the 15)

i added another (hayden) trans cooler to the front of the condenser...put some cushion between them

 

So I got my temp gauge installed, and opted for installing it to the governor test port as I saw that recommended on another forum and a) wanted the most accurate reading and b) didn’t want to hack into my lines. However, after about 15 miles of driving the temp gauge only read about 160F, and seemed to mainly creep up when stopped or in park. Was this the wrong move? Or perhaps is there a better test port to install it in? For reference this is the pic from the service manual I used:

 

A test port is just that, For testing pressure. It doesn't have flow so you are just reading the temp where it's located. You don't have to hack the line just install a "T" fitting between the trans and existing line.