ATF Cooler and Towing Questions

Thanks, appreciate it. It's the

$59 Hayden 679 Universal 11” Rapid-Cool Add-On Transmission Cooler to Enhance Cooling (not for direct replacement of the factory unit)

Hayden 679 cooler, which is in fact plate and fin construction. The build quality looked pretty good, but time will tell. That being said, Hayden is pretty well known for their coolers. The instructions for the cooler did indeed say to route cooler inline with the integrated radiator cooler for optimal performance.

 

i reconnected the radiator to the trans circuit today. It warmed up to idle temp MUCH faster than the other day. I tried putting it in temp check mode, but the problem was that it indicated it was at the correct temp for checking the fill level in under 5 minutes. The ambient temp was somewhere between 75-80degF. I reconnected my BullyDog tuner to check the tem and it was only at 98degF, which is a problem given. The recommended check temp is between 115-130degF per Toyota. I did away with the temp check mode altogether and just used the tuner to check the temp. After reconnecting the radiator, the trans fluid ended up being approx 8-10oz low it seems. Everything seems to be running well now. I have errands to run on the other side of Tucson on Tuesday, so we’ll see how it runs then. Our next trip with the camper is in just under 2 weeks at Alamo Lake State Park, so I’ll update after that on how the new cooler works out. Thanks so much for the help and advice! Perhaps we’ll meet at camp somewhere!

 

Awesome to hear. Let us know how temps are with towing and general day to day unloaded, always good to have data.

As far as the temp check, its best to do it on a stone cold truck, start it during the process to put in temp check and let idle, this will get the trans up to temp without tripping the temp check mode prematurely.

 

Off hand, do you know what temp the ATF dash light/ATF temp mode is checking? Is it at the torque converter sensor or at the transmission sensor?

 

Hayden has been around for years and is a high quality cooler. I installed one on my truck when I got a camping trailer in the early 80's. So are Tekonsha and B&M.

I believe the main reason they recommend keeping the radiator tank cooler in series is to prevent the possibility of over cooling the fluid, but honestly it's hard for me to imagine that ever happening. Over the years I have started my vehicles after sitting overnight at up to -25 F at times in central and northern Maine, and the trans has always engaged when I put it into "D". Maybe would engage and up-shift slightly slower, but not much, and they shifted normally after a few minutes.

 

Looks like the window is 115-130 degrees and it wont go into check mode if fluid temp is above 86deg. Temp taken from the Pan as thats the logical spot for such a check.

 

I agree that would be the more logical spot, I'm just curious if anyone has a definitive answer, as well as about the physical location of the two sensors. I guess I should have taken a closer look at the valve body when I had my pan off lol, but just curious if anyone knows where the physical sensors are located.

 

That information will be nice to see when you take take your trips: when you are not towing, and especially the difference(s) when you are towing your camper.

 

i think the temp light comes on at like 280deg lol.
I also have large cooler with fan. My normal temps are right under 200deg in so cal. if i am towing (up to 6k in my truck on 35s) and i am around 230-250(if i get to 250 i slow down)

 

Mine comes on at 100*F pan temp. Pretty sure I have read there are two ranges that vary based on the year or something like that. Either way I dont think 15 degrees off is a huge deal.

Looks like the two blue connectors?

 

I discovered that I should have been pulling our trailer with a weight distributing hitch rather than just a standard ball hitch, so I picked up a used Curt WDH. It did not come with a sway control bar. We have noticed a little "wagging" at times as we're traveling on the freeway. Should we be using a sway bar? I was looking at the Curt 17200 on Amazon for $58.65 (only because the rest of the setup is Curt) - linked below. What are your thoughts?

$55 CURT 17200 Trailer Anti-Sway Bar Control Kit , Black

https://www.amazon.com/CURT-17200-Sway-Control-Kit/dp/B000HLO7QA

 

Have you towed with the WDH yet? I bet just that alone will solve lots of the swaying just by nature of how a WD hitch functions and the extra friction during turning they create. Also will allow you to load more gear at the front of the trailer to get some more tongue weight to help that as well.

 

I'm surprised that a popup is walking around on you at all. Mine has never done that.

That being said, I personally think that sway control is a must-have if you run a WDH. Because it transfers some of that tongue weight and redistributes it towards both the front axle and the trailer axle, it changes the physics just enough that it could introduce a little bit of a wiggle-butt.

I say buy and install the Curt.

 

it might be walking around due to how you load the trailer too, IE, not enough tongue weight.

 

I roasted my tranny by overheating it!