Tranny temps

I posted sometime back re:tranny temps. Just checking I any new info. My Glowshift gauge reads 100-120 normal driving with sensor located 6” before aftermarket cooler. But, 200 degrees coming out of tranny. Quite a difference. What should normal, unloaded temp be?
Thanks again.

 

200* out of the transmission is not out of normal for normal driving off the convertor, this is right off the torque convertor and this is where the heat is generated in the transmission. Towing will raise the temp quite a bit. My Dodge diesel 4X4 will normaly run 150-160 around town, towing the 5th wheel up a grade 250 is not out of the norm and backing off the throttle just a smidge will drop that 20*. There isnt much you can do about the temp coming out of the transmission and knowing what you know now, just dump the fluid in the pan every 20k-30k and you should be good. Fluid is relativley cheap compared to a trans overhaul... my transmission guy is telling me that it is over $1k per speed. An Allison 5 speed is well over $5k to go through. In the future these modern trucks with 8 and 10 speed transmissions, an overhaul will mechanically total the truck.

 

FWIW these were taken from the OBD2 using Bluetooth dongle and fusion app on a iPhone, I don’t know where OBD is reading temps but these were before and after adding an external cooler is series with the radiator. Both runs were done on same stretch of highway on 95 degree days.

 

Very good! Thank you so much

 

Haha I have the same setup, glowshift gauge with a 10x10 cooler up front will the radiator cooler bypassed. Those are perfect numbers. Anything over 200-220f for more then a minute or 2 is a problem.

 

Here is another way of looking at it.


https://www.tacomaworld.com/threads...t-gen-edition.138573/page-11103#post-30093955

 

But I would like to see higher temps, like 160-170 which is the temp closer to the transmission. I could relocate sender back down the line, about 6-8” from transmission and I’d get what I want but I did the easy way, put sender in rubber hose section of line up near cooler. I didn’t dream the temp would drop 50 degrees in the line right before the cooler. But I was lazy that day. Thanks guys for the info.

 

Tacoman2001$,
Where is your sender located? What temp do you get just normal driving, not towing? Also, is tranny torque converter locked up if towing with Overdrive disabled? Just trying to give my little truck all the help I can. Has 376,000 on Speedo but runs like a new one!

 

When I say ‘towing’ I mean less than 3500 lbs.

 

My temp sensor is right before the trans cooler. Normal temps are around 100 to 140f maybe up to 160ish in the summer if I'm not going up big hills. The torque converter is forced to lock up above 2200rpm. This is why people tell you to turn OD off, with it off the truck is forced to Rev above the stall speed and lock the converter. The ECT button can also help as it will hold the rpm higher. I would not worry about your trans temps. The fluid gets hot enough in the converter to boil off any water and clean the fluid.

 

Thank you so much. You said exactly what I wanted to hear. I guess I worry too much but I try to think ahead and take care of my truck. Has lots of miles on it but drives perfectly. 2.7 is good little motor.
Again, my thanks for info and advice.