Transmission cooler or not Thread

This is with or without the aux cooler?

 

With the chase aux cooler kit. Hayden heat exchanger. I’m glad I added it. Before I installed it I would see temps in the summer of 230+ sometimes just commuting with no load.

 

Towed my 6k lb travel trailer out to the camp site today . trailer loaded with gear and firewood in the box of the truck . Ambient temps were 30 degree Celsius up here in Canada . Towed in s5 , Temps peaked at 210 but seems to live around 200 to 205 with my

$52 Hayden 679 Universal 11” Rapid-Cool Add-On Transmission Cooler to Enhance Cooling (not for direct replacement of the factory unit)

Hayden 679 cooler setup .

 

Noticed something shortly after the install that was slightly alarming, but I feel like my thinking is straight after I calmed down from thinking I ruined my truck. I wonder if anyone would have some insight.

I pulled off the road about 30 minutes after my cooler install and it looked like water was seeping out of the rear of the transmission pan seal. It was a significant amount and was making a puddle on the ground. Thought for sure I had somehow managed to damage the hockey puck during the thermostat install to the point where it was dumping engine coolant into the transmission, even though I was very careful to follow torque specs. I stuck my hand under it to catch some - it was warm, completely clear, tasteless, not oily, and exactly like condensation off the air conditioner coils (aside from warm temp). Except I swore it was bubbling out around the transmission pan gasket.

I had my scan gauge on the whole drive - transmission pan temps never went over 190 and coolant temps were 195-200. No irregularities in shifting or problems with overheating, trans or engine.

Engine coolant reservoir was clear and clean, so was the coolant sitting under the radiator cap - no evidence of oil contamination. Coolant levels were perfect, no signs that I had lost a bunch into the transmission. Pulled the overflow plug on tranny and took a sample, fluid was still clear and bright cherry red. Just judging by the amount of water dripping off the transmission, I would have had a pepto bismol looking foamy mess spraying out of the breather if that was actually the case. I saw no signs of anything leaking around the thermostat/hockey puck.

I can't for the life of me figure out where all that water would have been coming from. It looked like condensate, but I just don't see how it could have come back from the AC lines at the front of the truck. It has since stopped and I haven't seen it again.

 

Its exactly what you mentioned , Condensation from the evaporator core , totally normal when you have your a/c on . There is a drain tube on the passenger side lower firewall that allows water to drain out from the hvac box .

 

Nothing says concern about your 200+ degree trans cooler like sticking your hand in the fluid....

seriously, you could have really fucked up your hand.

 

Same temps I saw pulling my 5Klb boat at 97F to Florida, curious what speed were you going? I was going about 73-76mph. I also have the Hayden cooler.

 

It's a miracle I made it out alive without the advice of people on the internet.

 

I do about 60- 65 mph when towing my trailer , rolling hills , nothing too steep

 

Cool I prefer the engine RPMs to be 2400, seams to minimize shifting and keeps oil pressure up (I use the 0W-20). S5 puts me at 73-75mph to accommodate 2400rpm. With the Hayden cooler transmission temps concerns are a history. I even pushed to 78mph and my temp went from 202-204. 78mph and trailer starts to feel a little light. Same happened when pulling with a 2017 F250.

 

Your best to lay out your daily regimen here so you can be advised if it's safe or not.

 

You are a danger to everyone else on the road!

I had recently started lending your posts and their content greater weight. On your advice I bought a transmission cooler kit made by someone on a half ton truck forum (very well made and professionally packaged).

Now I'm not going to install it after what I just read. I'm returning it.

 

Indeed!

Lettuce critique in excoriating detail. Begin now, plz.

 

No worries my trailer tires rated up to 85mph, tires loaded at 60% of capacity. I have no idea of the speed limit I-10 from Houston to Destin but if your not doing 75mph plus you are getting pushed off the road....

 

I bought my truck knowing it did not have a cooler. I ordered Nick’s kit and will be installing it in my 2021 before I hit 1k. It’s peace of mind for me, nothing more. I’m keeping this truck for a long time and plan to tow a 5k travel trailer all over the US.

 

Is there a point mileage wise where it’s not worth it? I have 28K on my 2020 and am a little uneasy seeing 220 in summer just driving highway/city unloaded.

 

If you don't tow, always drive on flat land, or never 4WD it might not be worth it. I feel that the cooler is a no-brainer for most Tundra owners.

 

I tow 6x10 enclosed trailer 2-3 times a month. Probably 3-4K. But I’ve observed while driving highway temps over 220 steady. I can’t imagine I’ve done damage in 28K miles but just wanted some other input.

Probably don’t need, but it would give peace of mind.

 

I don't think that you did damage with that weight. I was seeing 240° with an empty dump trailer around town and that was enough for me. Keep in mind that there are hills everywhere around me.

 

Did you install your own? Doesn’t look terribly difficult to install.

 

I did install it myself. It's not too bad. Just watch the videos and take your time. The fluid level check procedure is a WTF when reading about it but it is really not tough at all.

 

Which app is this?

 

OBD Fusion

 

Cool. I have OBDLink and will try it out as they seem to be the same app.

 

My buddy has a 2020 and he owns a tree company and towes a heavy loads he said it over heated when going in reverse up a hill......I plan on getting a trailer in a few years and would like to know my 2020 will be ok. Thansk for all the info guys.

 

Yes sir. If you have the 5.7L both the Setrab and MHX kits will fit.

 

going backward unless you engine temp gets hot and the coolant fan kicks on you aren't bringing any cool air across cooler, they will all run hot. you need to trick coolant fan to kick on and pull air across trans cooler

 

Bringing this back based on this new post - a sign of things to come for these 2019-2020 Tundras that are more than mall crawling grocery getters?
https://www.tundras.com/threads/rip-pro-long-live-the-limited.16842/page-26#post-2441176

 

If you tow with a 19-21 Tundra, especially in hotter climates and in places where the road isn’t flat this really is a no brainer. Anyone who blindly believes the statement of one engineer who is more concerned with cost savings than doing the right thing they are simply gambling. The tranny in our trucks is stout as hell , but heat will kill anything eventually. It will take more than 2-3 years to start seeing the failures, but I believe they will start surfacing. I will be installing a cooler on my 21.

 

It's easy and inexpensive insurance.
Transmission Cooler ~$40
Thermostat ~$140
Quality Hose ~$70
Simpson Strong Tie ~$3