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Trans temp?

It got up to 210 or so on up hill pull. Has it's own cooler with fan not run thru radiator. Seems warm to me
 
Getting into the low to mid- 200's for shorter periods of times shouldn't cause any issues at all (heavy acceleration, pulling a steep grade) as long as the normal cruising temps are below 200. When I say short periods of times that can be for several miles at a time....not like jumping to 250 for 30 seconds is going to cause issues. If you stay under the 250 range it's mainly just the fluid breaking down faster and needing more frequent changes. If you start regularly getting into the upper 200 to 300 range you should keep an eye on it and start doing something about it. On my 2500HD the fluid never gets above the engine temperature, which is pretty reasonable considering it is running through and around the engine radiator.
 
my th400 will get up to 230 in the hills at highway speeds and it's 180-190 crawling around. Temp sensor reading is at the pan.
 
It just so happens that I was watching my trans temp on the programer in my power stroke yesterday. Climbing steep hill for a ways temp got to 210 and the dash gauge never got close to high temp mark. That made me feel a little better.
 
So what's the process to get a readout on the trans temp? I got an r400 that's probably not going to last much longer behind my 454 but I'd like to have a temp gauge set up for when I make the move to something stronger.
 
So what's the process to get a readout on the trans temp? I got an r400 that's probably not going to last much longer behind my 454 but I'd like to have a temp gauge set up for when I make the move to something stronger.

If you want a pan reading derale makes a kit, just need to drill a hole in your pan for the sensor.
 
Where is the ideal place for the sender? I have mine in the pressure port on my 4L60E, and in my old AOD.
 
i have mine in the hot line out to know just how hard i am working the trans . its in the remote filter unit port just for the sender . so my fluid is filtered before the cooler in the rad . just the way i like it nothing wrong with pan for average temp . but my truck is a work truck / plow truck / trailer pulling vehicle .
 
You really should run it through the radiator and then through any external cooler and then back to the trans.

The other thing you need to make sure is any of the fittings that are in the line and not restricting the flow. I had some aftermarket fittings that were probably less then a 1/4 inch ID in the bends. Once I removed those and put in some nice size russels fittings, probably -6s I'd have to check, the trans temps went way down. It rarely even gets over the 160 mark.

I too have an external cooler with a fan(B&M). I run to the bottom of the radiator then out to the low side of the external cooler out the top and back to the transmission. I've read going low to high helps keep out air and forces the fluid to use all of the cooler. I also run a large sump aluminum pan which I drilled and tapped for my temp sensor. YMMV

edit for pic

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I used hydraulic lines instead of steel tube. Should be good in size, but I will check. Don't see how running it thru radiator will help.
 
Don't see how running it thru radiator will help.

For me it was the difference between cooking the fluid and not. It also took a long time for the fluid to warm up with an external cooler which is hard on the trans as well.
 
Pan is the best place for a temp sensor, period. Only part of the fluid gets routed to the cooler, NOT all of it. The cooler circuit is run in parallel with the rest of the trans, so some of the fluid will be recirculating back to the pan rather than to the cooler. The pan is where the pump is drawing fluid from, and that's the important number to know - what the temp of the fluid going back into the trans is.
 
I agree, but until I swapped to DD gauges, I had a sensor mounted at the external filter prior to cooler. I noticed changes in fluid temp that I don’t see anymore now that it is fed from the ecu.
 
I used hydraulic lines instead of steel tube. Should be good in size, but I will check. Don't see how running it thru radiator will help.

The radiator will both cool and heat the fluid. When the trans is hot the radiator will cool the fluid even if the truck is running 190 degrees.

If your trans cooler fan fails and you are in stop and go traffic you WILL cook the trans.
 
I used hydraulic lines instead of steel tube. Should be good in size, but I will check. Don't see how running it thru radiator will help.
Running it through the radiator is a liquid to liquid cooler. It is 7 times more efficient than a liquid to air.
 
Running it through the radiator is a liquid to liquid cooler. It is 7 times more efficient than a liquid to air.
Hmm..... Yeah.... Buy the liquid is air cooled. I'm not sure I agree with that theory. Meaning a radiator trans cooler is better then a stand alone.
 
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