I have a Mag-hytec tranny pan with a tapped sending unit port in it. Currently I'm utilizing the test port on the drivers side of the tranny for my guage. What in your guy's opinion is the difference in guage readings between these two points. Thanks for any input or opinions.

 

I think most use the test port with no issues. You might try and find Mark Kovalsky, and shoot him a PM. He could tell you for sure. If not, could you run 2 gauges temporarily to watch the difference in the readings?

 

Test port is actual trans temp of working fluid. Pan fluid is going to be cooler.

As a comparison, it would be like your coolant temp sensor. It's mounted to read coolant temps as they come out of the engine so you see the working water temp. Having a trans temp sensor in the pan is like reading coolant temps from the reservoir.

 

Leave it in the test port. Like Curtis said, the temperature from the pan are not as useful as working temperature at the test port.

 

OK Gotta do the pot stirrin thing here
Someone surley has tried a sensor in both locations what is the diff in the temp readings betweeen test port and the pan?
Reason I ask mine in the M/H is in the pan.
It normally runs about 140 to 150
So do you think it would be like 170-180 actual working temp ???

 

Mark had mentioned seeing sensor readings at more locations than you could dream about. Hopefully he'll come along and chime in on this.

 

Read Mark's comments in post #7 of this thread.

https://www.ford-trucks.com/forums/7...mp-sender.html

 

I have my gauge in the test port and also watch the temps in my Scangauge which gets its info from the trans fluid temp sensor in the solenoid pack. Easy driving the temps are very close. Flogging the truck the TFT in the pack are 15-20 degrees hotter. Use the test port, its tucked up higher from road hazards and already there.

 

I have had both and there is no real differance between the two to worry about... Keep it under 230 and your golden.

 

When you guys are at idle in park, what are your normal tranny temps? Outside temp 85*

 

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.