Here is some info I got from an email from John Wood as to the placement of the tranny temperature sender. I found it interesting. Do most of us use the pressure port because it is easier?


"The pressure port is line pressure and the hottest point in trans other then
the coverter.
It will work ok there however I do like the sender in the cooler line for
real time temp
Thank you,
John Wood Automotive
760-356-9421
760-356-1734
----- Original Message -----
From:
To: <john@jwtt.com>
Sent: Saturday, March 29, 2008 8:57 PM
Subject: John Wood Automotive: Tansmission Temp Sender

> This is an enquiry e-mail via http://jwtt.com from:
>
>
> I hope you can find the time to answer my question. It seems that most
> people running e4od and 4r100 trannys are putting thier temp senders in
> the pressure port. The few tranmission guys, in my area, I have talked to
> say that this is not a good place for it. They say that not enough fluid
> flows through and you are better off welding a bung in the pan or running
> a manifold off of the cooling line. Where do you think is the optimal
> location and do you think using the pressure point will give "good enough"
> results? Thanks for you time. "

 

It is the easiest place to put it, as well as the place most people equate your tempature readings too. I have mine in the pan now, but have seen no real differance in the temps from one place to another.

 

Thanks, that is the kind of comparison I have been looking for. I noticed you recommended the pressure port over at the TDG but never said that you get the same readings in the pan.

 

Its more of a easy of install. The temps are not that differant, and for a guy that has never installed gauges before, removing a bolt is alot easier then dropping the pan!...LOL

 

As for ease of install. I figure putting a manifold on the cooling line would be easier than pulling the pan and welding in a bung. Another question, what temp are you running at during normal (average) driving on a 60 degree day? I figured the tranny should run somewhere around the water temp because of the cooler. Why is this not so?

 

Tranny temps should be 70-100 above air temps..

 

I've measured temps in the pressure port, the pan, and the lines to and from the coolers all at the same time.

The pressure port and the pan temps are very close almost all the time. The line to the cooler will have HUGE temperature fluctuations. When the truck is under load and the torque converter unlocks you can expect a quick rise, often to well over 200F. What are you going to do about that? It's normal operation, but to those that don't know a lot about transmissions it sure can be scary. Adding a large cooler won't help this at all.

I like the sender in the pressure port. It gives the bulk temp of the trans, not the hottest spot, which to me is much more useful. The temp in the cooler line is the hottest spot, but that doesn't mean much for the life of the trans, the bulk temp does.

If you are watching temps in the pressure port or the pan, 60-100F above ambient is normal, with some higher temps when the truck is working hard. If you are looking at temps in the line to the cooler 60-250F above ambient is normal.

I will point out from 2004-2007 transmission cooling was my job. I ran many cooling tests on the road, on test tracks, and in wind tunnels with vehicles with almost 100 thermocouples. I have a pretty good idea of how this stuff works. I'll bet it's a lot more than people that build some VERY good aftermarket transmissions.

Flame away.

 

Good post Mark!!!

 

Great info Mark. In my mind right from the horses mouth. LOL. I have an aftermarket pan that has a temp port built right in. That is where the original owner had put the sender so that is where I put mine also. I see pretty steady temps at 90 degrees over ambient. I just picked up last weekend a tranny cooler out of a V10 that I hope to put in soon and see those temps drop a few degrees.

 

If that cooler is used, flush it very good...