OK, while towing our camper(10,000 lbs) from central NC to Newport TN my Trans fluid held around 145 to 150. Outside Temps of 85ish, I40 from central NC to eTN is very hilly with a couple good pulls but nothing extreme. I have a 6.0 cooler and No OTW cooler. I know that's cool but is there any ill effects from the temp staying that low? Should I address it and what are some suggestions? Will an OTW cooler help or do I need something else? Thanks.. Phil.

 

Towing that much it's hard to believe that your gauge is accurate. If you have the torque app or equal you can verify that that is the same temp that sensor inside the transmission is seeing.


The trans has an optimum temp range for efficiency. Too low and mileage will suffer, which is a big reason during the winter our fuel mileage takes a hit. I forgot now what temp Mark K was optimal.

 

Well maybe I was putting too much stock in my new EV2s. It seems as though my Autometer stayed on the cool side too.. Does AE read Trans fluid temp?

 

That does seem low for towing. I think I read here on this forum (probably on a Mark K post) that you want it to at least get up to 175 to evaporate any condensation that forms inside the tranny.

I still have stock cooler and mine stays around 90-100 degrees over air temp. A little more in stop and go towing. I have not towed this summer in extreme heat yet.

 

AE should read trans temp. The ideal temperature is 170F. Running 140-150 isn't going to hurt it, but I really don't believe that is the actual temperature.

 

I doubt it also mine pulling 10k in nearer to 195 in town

 

Pulled basically that same area Sunday. I have stock cooler and otw. I stayed around 175-182 to Chattanooga. Almost the same load with our TT.

Useing the ScanGuage 2. FYI

 

Thanks guys, I'm gonna see what AE shows this weekend and compare it to my EV2 and go from there. I'll report back with the results.

 

I run almost exactly what temps your running when towing my 12k Toy Hauler. I have a 6.0 trans cooler. Since installing the 6.0 trans cooler two years ago and towing about 20k miles in outside temps over 100 I have never gone over 160 degrees. When I first installed my gauges I actually tested the trans sending unit and it was right on. Running a 6.0 cooler you will be running cooler temps. I pretty much run 60 degrees above outside air temperature.

 

Why not aim a IR heat gun at the side or bottom of the trans. pan and see what that tells you?

 

Trans pan temp is going to be anywhere from 10-20 degrees off what the temp may be inside at the trans. I have a temp probe in my trans pan and it runs about 10 degrees cooler than the trans temp from my SGII on the OBDII port. I also have an issue of running too cold in the winter as my 6.0 cooler driving around keeps my temps in the 130 range in the winter unless I cover it up a little to bring the temps up. It is suppose to be 110 here today and while I don't plan on going anywhere, the 6.0 cooler sure does help on days like these.

 

I agree on those hot days it's kinda nice. Our winters are pretty mild so I don't think cooler temps are a problem. Although I wonder why snakedoc who is also running a 6.0 cooler is running so much hotter? I wonder what it was running before the 6.0 cooler was installed?

 

Everybody is describing a different scenario with different hardware, and each difference has a profound impact on the temperature. The only scenario that was close was submitted by petrokiller - but he didn't have the same cooling hardware. Snakedoc towed in town, which is a torture chamber for transmissions. The open road has the torque converter locked and air passing through the cooler. What about humidity? Air conditioner on or off? Driving habits? What was Cruise Control set to?

I ran my normal run with 106 degrees F, no humidity (wildfires nearby), and A/C on. Everything I have with a gauge was running hot that day... it surprised me how much the EGTs were effected.

 

Phil, you could install a derale t-stat. It has a bypass valve so that the cooler is out of the loop when the fluid temp is too cold.

 

Humidity benefits cooling. The air is denser so it can absorb more heat from the coolers. At Ford when we ran cooling tests there was a maximum humidity for the test to meaningful. If the humidity was too high we didn't test.

Humidity will also lower EGT. It is the same as injecting water into the engine, but on a smaller scale.