cwgtex

Alright, I know this topic has been covered several times, but I cannot find a definitive answer. The two main locations for installing the transmission temperature gauge are at the factory test port and in the hot line going into the transmission cooler.

Obviously the latter option sounds better on paper. But in a real world environment, how much does it actually matter? Do you actually see temperature increases sooner? How much difference does it make in degrees?


Sender Extender

http://www.dieselmanor.com/dm_products/fittings.asp


Cooler Line with Sender Port

http://www.dieselmanor.com/dm_products/DM-CLG3.asp


My main question I guess is it worth it to spend $78 when an $18 part will work just as good?

soulezoo

I can tell you, from personal experience and learning the [I]hard[I] way, that the test port is the worst place. First, that is generally left over fluid that sees that port and the temp being shown is not reflective of what is going on there. Second, there is a little piston in there. For me, the first warning was when my gauge went out, took it to the place that installed it and they repaired it by installing a new sending unit. The one in there looked like it was hit with a hammer! The shop owner couldn't believe one of his guys would install that like that. The second one took out that little piston...

The best place is the hotline and it gives instant reading and you can watch it go up and down with immediacy. It is also the point of the hottest temps to be seen in the tranny... so if the fluid is ok there, it is ok everywhere else too. Unlike the test port or the pan. It was a pretty big difference, 50-60* worth, between hot line and test port.

TonyB

There is a bit of contention on this topic, as you collect opinions.

My perspective: The hot trans-cooler line is fine fo city monitoring. It will help remind you when to put the trans in neutral, when stopped in traffic.

The trans pan temp will give you an indication of when you have a problem or to shut the truck down, and let everything cool down. I have not had to do this yet, even when towing in >110F weather!

I monitor both.

Oh, and the test port will only give you transmission case temperature; NOT fluid temp.

Tony