transmission operating temperature
 

Pretty sure this was discussed before when the trucks were younger, but now from some time and experience I would like to know how those numbers are holding up and if there's a Ford reference sheet of some sort.

What's the recommended operating temperature that our transmission should be running? What are the low & high thresholds? From normal driving, towing, 4wheelin, etc...

2004 5.4L Lariat SuperCrew (4R70W transmission)

Anything between 180 and 220 should be fine.

Many moons have now passed. Some of us still hold on.

I installed an aftermarket cooler, along with a Mag Hytec DD pan. All in the interest of cooling.

I can't tell if it has helped or hurt the truck. But I still have the truck, and haven't had transmission problems yet.

With the ScanGauge II reading the transmission fluid temperature via OBD II port, where is the sensor? Am I seeing the temperature inside of the transmission? Is that the temperature of the fluid before it goes out to the cooler, or the temperature of the fluid returned from the cooler? How much of a difference is that from the temperature of the transmission fluid in the pan?

I'm not any kind of mechanic. Just a guy who drives his car, and has a set of wrenches. I save $19.95 on an oil change......but spend $100 buying my own synthetic oil and K&N filter.

The sensor is in the solenoid body. The solenoid body is in the pan, but raised from the bottom.The sensor shows a good average temperature inside the transmission. The fluid in the pan is the coolest part of the transmission. The fluid leaving for the cooler is the hottest point. The sensor reads between these two extremes.

Thank you Mr. Kovalsky. Thanks for being here to share your knowledge. According to your "Join Date" of May 2000, you have been here almost 20 years to help guys like me who don't know much.

[QUOTE=glc;5243070]Anything between 180 and 220 should be fine.[/QUOTEIn case anyone may be interested, these are a couple of shots of my ScanGauge, with TFT being transmission fluid temperature.

https://cimg0.ibsrv.net/gimg/www.f15...771e1f2ce8.jpg
https://cimg7.ibsrv.net/gimg/www.f15...c3d5d57c04.jpg
https://cimg2.ibsrv.net/gimg/www.f15...592ac25dba.jpg

What were you doing in the rig prior to or during that pic? Looks like your rpm is just idling for the most part?

I can pull my #5000 TT up a 10 mile 5% grade with the outside temps in the mid 90's and I'm in 4th gear pulling some 2500 rpms going an easy 60 mph and the most my trans temp gets to is *210 at the top of the grade (west bound I-90 in Vantage).. The highest my trans temp has gotten is *225 while going up a switch back kind of road with the outside temps in the mid 90's, but I was only able to go 20-25 mph and was in 2nd/3rd gear due to the grade and the switch backs...

Even in my old 97 F150 with the 5.4 and E4OD trans, the trans temp only got to around *210 going up the same 5% grade towing the same TT.. Only difference was, I was in 2nd gear, pulling some 3500 rpms going around 50 mph and not much left power wise.. I put a trans temp sensor on the trans output line just before it went into the rad on one of those pillar gauge pods... Along with a water temp gauge.. The water temp didn't go much above *210 either..

So, don't know if what you are seeing is good or not depending on what the conditions were when it was taken?

Good luck!

Mitch

The photos were taken in with the transmission in "P", after driving around all day.

I have one of those "point & shoot" laser thermometers. The inlet of my auxiliary cooler, after the fluid has passed through the OEM cooling system (radiator) is about 135-140 degrees Fahrenheit. The outlet of the cooler, where the return line delivers fluid back to the transmission, is about 110-115. The fan on the cooler is suppose to activate at 175 degree Fahrenheit, and the fan has never turned on. This means that after fluid has passed through the radiator, it is never at 175 or higher when it reaches the cooler. So for whatever it is worth, the fluid is about 100 degrees cooler going back into the transmission.

That is a consistent temperature range for my truck, for as long as I can remember. I'm the original owner. ScanGauge II has always shown 200 - 225 after a day of driving. If I am just commuting, Temp will always be be about 160-185 by the time I get to work. I try to exchange the fluid when I can remember to. Sometimes I just don't have as much time, and it's just drain the pan, clean the magnetic drain plug, refill, and go. Not so good, but better than nothing.

According to B&M, you should monitor fluid temperature as it leaves the cooler and returns to the transmission.
https://cimg4.ibsrv.net/gimg/www.f15...eeb9411b5f.jpg

https://d1y6jrbzotnyjg.cloudfront.ne...2XWKZ35EOVO4XA

Just driving. If I cruise around all day, I see temps from 200 - 225. In overdrive, the coolant was 177, while ATF was 222. That's fresh fluid, as I performed a fluid exchange just a few weeks ago. Exit the freeway, and ATF temp comes down. Park the truck, and coolant goes up as ATF goes down.

Maybe the 35" tires are a little harder on the transmission. I don't know. But the truck has always shown those numbers. I'm the original owner.
https://cimg4.ibsrv.net/gimg/www.f15...f757ba0a02.jpg
https://cimg5.ibsrv.net/gimg/www.f15...031d745130.jpg

Ever since I got my Edge, I've kept my trans temp as one of my five parameters that I keep an eye on. The highest I've ever seen mine is 166°. That's after cruising at 70-75mph for quite a while. Around town (the vast majority of my driving) the temp stays in the 140-150° range. But being that mine is the 8200 and not a regular F150, it has the stock heavier duty trans cooler...

The 6 and 10 speeds (6r80 and 10r80) run 190-220 and have a thermostat inside. The four speeds seem to run cooler at 140-170 average. Not sure about a thermostat in those. All steady state operating temperatures.

It is called the Fluid Cooler Bypass Valve, Item 8, Part No. 7H322.. The valve allows the transmission to warm up to correct operating temperature. If the fluid is cool, the valve is open, which allows fluid to circulate back to the transmission without going to the cooler. Hot fluid closes the valve, and flows to the cooler. Kind of like your thermostat, which pops open as the coolant heats up. The valve pops close, as the fluid heats up. If it fails, the valve remains open, causing hot fluid to flow right back into the transmission without cooling.
http://www.monkeyview.net//id/431/de...out_cooler.jpg


I am thinking of removing it.