2019 5.7 trans cooler location

Did the pre 2019 models have a seperate trans cooler only if it had the tow package?

 

Yes coolers came only with the tow package.

 

This is what I figured but wasn't sure so figured I'd ask. I'm just confused why people are assuming that the way it is set up now is going to burn up the tranny even when not towing. I totally understand if you are hauling why you would want a separate cooler but if older Tundras without the tow package never even had a separate cooler I don't really see the argument since people with pre 2019 without the tow package haven't had a massive amount of failures.

 

The reason we...as in those who own a 2019 and up...are upset is the Monroney in the window said it had a cooler, in addition to my brother-in-law has a 2018 and runs 195 at most. Using the same OBD reader mine runs 220-230 Verified with my infrared thermometer on the brass fitting on the pan. Keep in mind this is without towing. Toyota claims they have figured out how to manage the heat without the cooler. The numbers don’t support their claims. I have tried to contact 2 dealers, but no one will return my call about this.

I’m planning on changing the fluid and having it analyzed. If it comes back great I’ll have to eat my words. The transmission shop I talked to about the numbers didn’t give me any extra confidence.

 

Trust me I wish the 2019 did come with an external cooler. The window stick says "eng/trans fluid coolers" so it didn't exactly lie since the engine and trans cooler are now combined. My point is simply that thousands of Tundra's pre 2019 did not come with a tow package and there for did not have an external cooler so must also run at the same temp as the 2019s do and have not had an issue and I'm sure many of those Tundra's that didn't come with a tow package have been used to tow.

 

The truck I bought said it had a cooler. I use it to tow my boat all summer and my Tundra is awesome for towing. The Tundra replaced a 2004 GMC Yukon that blew up a transmission pulling the same boat. I love my Tundra, but I am nervous about the temps without towing, let alone towing over the Siskiyou's at 100 degrees to Shasta.

 

I’m just Gona enjoy my truck. Lol.

 

I didn't read every page but it seems no one else has responded to this post. I wonder if maybe Toyotas move to remove the integrated trans cooler in the radiator has something to do with the fact that many people with not just Toyota but many vehicles with integrated trans coolers in the radiator have experienced the "pink milkshake" when the radiator inevitably fails and mixes the coolant with the transmission fluid. It would seem the new setup on the 2019 would not have this issue at all. Albeit at the risk of higher trans oil temps. An air to oil cooler is definitely more effective than a water to oil cooler but a water to oil cooler is still a cooler. The warmer as we refer to it in this thread is effectively a warmer when the coolant is warmer than the trans fluid but when the trans fluid is warmer than the coolant the coolant will carry away the heat the same way as a computer that has water cooling cpu or gpu chips does carrying the warmer fluid back to the radiator to be cooler by air. A true oil to air cooler that is separate from the radiator is definitely the better option but that was done away with long before the 2019. Personally I am in Boston and it is winter here so my stats are not complete but watching my temps the trans oil stays pretty much on point with the engine oil temps and has only gone over 200 when I am traveling above 65mph. I will continue to watch the temps though especially as the weather gets warmer.

 

It wasn’t integrated with the radiator. It was integrated with the ac condenser. But even that system had the warmer/cooler the 19+ have. There was no greater chance then that it would mix, and I think no chance now as it seems the 2 systems are closed off - 1 loop for coolant separated by a seal to the trans. Unless the seal leaking is what the other thread referred to.

 

OTW cooling is far from New. My '01 4Runner had it as standard.

Yes it works well until the radiator gets to around 10 years old, then the "Pink Milkshake" (cuz that is Exactly what the transmission fluid looks like when this happens) can occur. In short, the rubber seals between the trans cooler and engine radiator begin leaking.

Because the engine radiator has pressure, it's fluid leaks into the trans fluid. Transmissions absolutely do NOT like like, enjoy or want engine coolant, it very quickly (less than 100 miles) can soak up into the clutch packs and the trans is TOAST. Happens every day to these types of systems. Many manufactures have used these method since the 80s, many fail, many don't.

So on TR4.org the standard is to replace 4Runner radiators every 10 years, they're cheap, $99 and 3 hrs work.

So, IF that is what Toyota has gifted us 5.7 owners be on guard for this eventuality. Not a matter of If, its WHEN.

More information here: Luck and enjoy all. : ^ )))

 

Well, well, well, looks like 3rd gen 5.7 run really HOT trans temps! Been reading on here many folks get well over 200 just traveling on 80 degree days at highway speeds on level roads. Not Bueno.

So I'm going to do this (once spring comes around) "pinning" thing: See thread #24 on this page: https://www.tundras.com/threads/transmission-temperatures.3236/

May add an external cooler with cold weather loop if the pinning doesn't bring the temps down to a reasonable 160.

Luck all. : ^ )))

 

The 2019-2020 does not have a tranny thermostat if that's what you mean by pinning.

 

On all Tundras since 2007 (5.7L, 4.7L, 4.6L), Toyota design policy has been to get ATF to approximately 195 degrees as quickly as possible. You can argue that you're smarter, that cooler fluid is better, that they did it only for fuel efficiency, whatever, but Toyota is designing and building the transmission.

How do we know that they think 195 degrees is ideal for their transmission? Since 2007, ALL Tundras, tow package or not, have come equipped with an ATF warmer/"cooler" mounted on the side of the transmission that uses engine coolant (~195 degrees) as the warming/cooling medium. It warms the ATF with coolant up to 195 degrees, and then provides some cooling once ATF temp exceeds 195 degrees. The fact that Toyota added a tow-package thermostat and auxiliary ATF cooler (top section of AC condenser) in 2010 (4.6L) says they didn't think the warmer/cooler on the side of the transmission provided adequate cooling to maintain their reliability goal. What changed for 2019 to change engineering thinking?...Where this thread began.

If you have the thermostat (2010-2018 tow package), you can pin it. You may be able to achieve ATF temps of 160 deg (and lower) in Boston. Just don't be surprised if your transmission doesn't shift as smoothly and predictably as it did before you pinned it.

 

JohnLakeman - I completely hear you. It all makes sense as far as a quicker warm up to 'normal' operating temps for all fluids is ideal for fuel efficiency and other smoothness aspects. Don't disagree Toyota engineers are far, far smarter than I.

Based on my experience with 4Runner trans temps, once we get into full summer here in central texas, I'll monitor trans temps on my 5.7 carefully with torque. If during towing on our hilly terrain I experience temps above 200 during ambient temps of 100 or so, I will do something reasonable to lower them to a steady below 200 range. I simply cannot stand any of my trans getting above 200 constantly in stop/go, towing and just plain 100+ weather we have here for about 75 -90 days (on average). Sure I don't want 135, just a nice reasonable 175-185, Tops that is.

I appreciate the feedback and dialog, good site for information sharing. Luck and enjoy all your Toyotas. : ^ )))

 

Central Texas? Sorry, I confused @Joe333x post with yours.

My opinion is that for 2019+, Toyota decided there was no point installing auxiliary coolers on all 2019+ tow packages if people were going to buy them as "must have" options on Cowboy Cadillacs that NEVER tow. There has been evidence here that if a Tundra sees mild daily driver service (like mine), Toyota's claim of "lifetime" AFT may actually be reasonable for the average original owner that drives like your grandfather (like me).

I believe Toyota decided to absorb the hit to their reliability rep on those Tundras that really do TOW. I believe Toyota has decided to save the money on the thermostat, lines, and stand-alone auxiliary cooler; in those cases where the transmissions croak at <60K miles, they're resigned to biting the bullet and fixing them under warranty. My opinion is 2019+ transmissions will have shortened service life compared to previous years at the ATF temps some have observed here on 2019+. Unfortunately, those owners that actually do tow ARE going to see premature transmission failures, possibly repaired under warranty, but certainly soon after the warranty expires.

As I said earlier in this thread, if you have a 2019+, and you tow with it:
(1) Monitor ATF temps closely. I am in the process of working up an Ultra-Gauge page for towing which I'll share.
(2) If ATF temps routinely exceed 220 degrees, I would regularly (every ~15-20K miles?) send ATF samples off for analysis,
(3) Based on analysis, change ATF frequently using full synthetic fluid (precludes WS fluid),
(4) If ATF temps are routinely exceeding 230 degrees, I would retrofit an auxiliary ATF cooler using an appropriate 2010-2018 Toyota thermostat (5.7L, 4.6L are different).

 

Just ran across this thread. What a kick in the balls. Thankfully I leased my 2019 because I’m towing the sh*t out of it - literally almost never disconnect my 6500#ish work trailer - even on the weekends... always in tow-haul mode. A long time ago my brother in law worked for a big transmission supplier on the west coast. I remember him telling me over and over - heat kills transmissions faster than anything else. And the strawberry milkshake of death is very real and very common. Why Toyota? Why????

 

Toyota made a big mistake, but with their mistake also gives us 19-20 tundra owners a opportunity to mount a external cooler that does not have to route through the radiator. This will make it a complete separate system unlike the 2018 tundras.

 

I respect your opinion and I BELIEVE that you're correct. However, as the primary reason I bought my Tundra was to tow a travel trailer to the mountains a few times a year, I HOPE you're wrong. If I wasn't going to tow anything, I probably would have bought a 4Runner or something else that would fit in my garage and be a little better on gas, rather than a Tundra.

 

As johnlakeman said, transmissions are designed to run a little hotter now. There is a chart on the internet that says 200 is bad, but it’s also years old. Tundras are designed to run in the 180-200 range, at least the ones with the cooler based off when the thermostat opens. I think the overheat light comes on around 245 or 250.

I’ve read that it’s the new synthetic fluid that allows it to run hotter and for mpg reasons.

 

Maybe there has been a paradigm shift in clutch facings and other wearing materials to allow them to run at higher temperatures, but as an engineer, that is hard for me to believe. Toyota hasn't said that to be the case...they're not saying anything. I suspect the transmission design will have less impact on service life than the degradation of the fluid. Valvoline says their full synthetic MaxLife will begin to degrade quickly after about 240 degrees, and you can expect synthetic blend WS to begin degrading well before that.

I have compassion for you 2019+ owners that tow. My objective has never been to intentionally "stir your pots". Experience will tell the tale. If you're concerned, follow the advice I offered above, especially the monitoring of fluid temperatures.

 

The pink milkshake I don't think is possible with the 2019 since the atf fluid doesn't travel up to the radiator. Is that not correct?

 

I thought it was ‘19s and ‘20s... and the ‘18s were different. But I really don’t know for sure. Had a few Honda products with the now infamous transcooler fittings. I hope this effects the fewest number of owners out there. It’s just a horrible, cheap design that screams bean counters over long term durability.

 

You are correct.

 

ATF never went to the radiator. It went to a trans cooler/ ac condenser. The same coolant that goes to the trans now went to it before 19/20.

 

No, ATF never went to the radiator.

 

How did the coolant mix with transfluid to create the "pink milkshake" in previous models?

 

Prior parts research indicates @timsp8 is correct. Since 2000, Tundras have never used ATF heat exchangers in the radiator tanks. The earliest models used stand-alone air/ATF coolers without temperature regulation. I believe some early (Gen1?) Tundras had a power steering fluid cooler in the lower radiator tank...that may have been the early source for "pink milkshake" (if red ATF was used in the PS).

There is a brass heat exchanger core inside the warmer/cooler that can leak fluid into the surrounding coolant.

In 2007, the ATF warmer was added to ALL Tundras to get temperature up to 195+ degrees quickly. (And, yes, the stated purpose is to reduce friction losses quickly and improve fuel efficiency.) In 2010, they added the thermostat to the 4.6L tow package to provide ATF temp regulation with the cooler built into the top of the AC condenser. That configuration became standard on the 5.7 tow package in 2011 until it was discontinued in 2019.

 

As @JohnLakeman said, it was separate 07-mid 10 offset on the passenger side. Then they integrated in with the ac condenser. You can see the lines on the passenger side of the cooler.

07-10


Mid 10-18


19-20

 

as the last picture shows, Toyota is 100% correct ... Biz guy doesn't tow you know. He goes to office, mall, grocery store, occasional hardware store ....

 

Curious to know if they also changed the set up on the new Land Cruisers?