No effing trans cooler?! I'm out Toyota

Going back to the frames issue , seems to me it wasn't Toyotas fault , but the frame producer, and also seems as though Toyota has taken very good care of alot of people with frame issues ,even to this day.
Coolers became more of an add on expense or cost for buyers , to kick prices up and start calling tow pkgs, For so many years majority of trucks never had coolers on them and they towed everything imaginable.
Also years ago in my off road racing days we added remote mount oil filters so we could gain an x-tra 2-3 qts of oil, and we rarely added trany coolers , but when we did again it was mainly for x-tra oil capacity , but now Toyota doesn't even feel you need to check tranny fluid level, so I agree the engineers have these transmisions pretty much bullet proof for what this Tundra is capable of , and we've even proven to ourselves they can go way beyond THAT!!!!

 

Okay I’ll give it a shot. They changed the programming for the transmission so that it will downshift in tow/haul mode instead of unlocking the torque converter. Most of the heat in a transmission is generated when it runs with the torque converter unlocked.

 

I have more peace of mind buying a Tundra than any other half ton. That same part of me has peace of mind installing a trans cooler which brought temps down on my 21.

Your comment is the first I’ve read that hypothesizes that they did something to offset the deletion. But given the insanely high temps some have reported on here from towing with no cooler (and from just driving unloaded with no cooler) makes me think it doesn’t quite add up.

 

Fair enough. I wasn’t just hypothesizing though. Mike Sweers said that in an interview I saw or read.

 

You are not going to 300 k with no cooler without thorough understanding of the system and it’s capabilities.

They also changed to R 1234 and a new condenser that supports it. This adds costs.
Might also be a new compressor but I haven't compared part numbers. Usually new refrigerant = new compression.
They also changed transmission mapping to reduce time converter is unlocked. This adds costs.

You simply aren't going to go 300k miles with no cooler unless the system was thoroughly analyzed and well understood. To argue that this decision was "from the boardroom" is basically saying its luck to go 300 k miles in the current configuration.

The configurations with a transmission cooler needed it due to the heat load from converter un-lock. Some trucks also had gear ratios higher than 4.30.

300k miles with no cooler is so far outside the realm of luck its silly to even debate it.

Everyone here, whether you are 'cooled' or not, should be thrilled the AB60F can go 300 k miles with 40F higher temps. What a badass transmission.


I'll also repost this here from post 447 above:

It isn't just the engineers involved in this. There is a host of considerations outside the engineering function. Engineering is there to support program goals and targets, and give program managers options.

The pattern that is repeated in situations like this is

Target condition
Current condition
Obstacles
Test, validate changes to overcome obstacles
Repeat.

Engineers are giving program managers options to work with for reaching targets. One of those targets was to integrate a R1234 condenser to support company goals for this type of refrigerant conversion (pretty typical in auto oem...like removing sources of lead...).

Engineers and program managers likely knew this change was coming down the pike for several years. Plenty of time to design some changes and test them.

The changes that can accommodate this, and appear to be present on the Tundra, are

• Shift mapping changes to chase lock up sooner, longer, and unlock only when absolutely necessary. This is the single biggest contributor to heat load. And the reason previous generations had an aux cooler.
• 4.30 gear standard...unloads the transmission
• Minor cooling system changes to keep coolant below 210F, and to support new refrigerant operational specs (pressure, temperature).
• There may be other changes we don't know about like fan clutch, or transmission component changes...

To explain this further, these changes were tested with removal of the aux cooler. The aux cooler removal coincided with a change in a.c condenser to move to R1234. If the thermal load from transmission was making it impossible for new condenser and refrigerant combo to work, then a deeper look was required. They may have known ahead of time that the transmission thermal load wasn't going to work with new refrigerant.

Reading between some lines between various videos with Toyota reps, it looks like they had a rather high target temperature range for fluid temps in realm of 250F. Not sure if this was the TQ or pan temps. To get to this knowledge that the AB60F can take this kind of heat likely took some further testing done over many years. They also likely considered that the fluid is a group iii oil and can withstand 280F (or greater for brief periods).

So with the new ac condenser, and the changes listed above, the transmissions, likely hundreds, were instrumented and tested to confirm/deny hypothesis that the aux cooler was needed to maintain target temps.

Changes like this are typically thoroughly tested, and the permutation is known or planned, well in advance. This occurs at all OEMs...not just Toyota. I'm betting from past experience working at an OEM in a design and testing position that this change was known and tested 3-4 years before it was finalized.

What engineers are "saying" is if given constraints x,y,z, then you need to make changes a,b,c (with each of a,b,c being a slew of variables like those listed above) and test them against known targets for a transmission, or a component like clutches, or seals, or gears.

Program managers (I'm guessing like Mike Sweers) then looks at the results of testing for options/permutations a,b,c. He has to decide which way to go based on many factors. One of these factors is how manufacturing will change to support each of a,b,c. Option c might be a lights-out option but if manufacturing can't support it, or the change to process is too dramatic, then option a,b is scrutinized. And so on...these evaluations are also considered in terms of larger corporate philosophy and long term goals.


Option a: new bracket, new air-oil cooler, new oil lines, new clamps,
Manufacturing changes needed: new drilling and tapping, new hose routing procedures, new QA/QC steps to check for proper hose routing and connection. Bracket dimension checks. need to get a vendor qualified and validated to make new cooler to Toyota specs. Even previous vendor would need requalification. Bracket manufacturing QC and procedures.
Design and engineering: Bracket material and anti-corrosion coating? Bracket mounting location? Will bracket interfere with any safety system performance? Both situations need testing to validate. Previous cooler location may not work with new condenser. Do we go with rubber or stainless tubing?
Change management: updating all BOM and repair manuals for new cooler. updating manufacturing procedures. Update virtual model of Tundra for new BOM and hose/tubing routing.
Program management: Is there residual risk that these changes in hose/tubing, routing, bracket, cooler, mounting, will create a manufacturing defect and how can we verify? (GM recently had an issue with their transmission cooler lines popping off in certain conditions...that would suck). Our FMEA indicates more tubing and hose = more opportunities for failures. Tundra already has too many engine coolant lines...

Option b: Do without auxillary cooling.
Manufacturing changes: new adapter plate. Remove procedures for previous routing and installing transmission thermostat and associated lines and finall connections.. No thermostat needed. No tubing and hose needed.
Design and engineering: We have a situation where the transmission thermostat opens up at 195-200F, only to have an aux cooler bring temps back down to 180F. The aux cooler is only needed when the converter runs out of lock up for extended periods. Can we change this? Final testing and validation of AB60F without aux cooler and shift map changes.
Change management: update BOM and repair manuals. and remove previous items from virtual model of Tundra.
Program management: Transmission runs 40F warmer but is within our temp targets that are well established for AB60F durability, and shift-map changes, and rear gearing, brought temps to an improved and sustainable range under our targets. We get less parts and less total change to manage. This translates to less waste and less opportunities for defects. Do we have any realistic residual risk with running 40F higher than previous configurations? If so we have ability to further tune shifting and lock up.

Basically to me the only way this makes any sense is if Toyota knew, absolutely, and completely, that the AB60F can handily sustain 40F higher temps.

It isn't a surprise to me that if a change can be made such that a system can work and meet targets with less parts, that Toyota would carefully consider this.

 

There are many, many, posts by knowledgeable members that indicate this very thing, in many other threads.

 

We are yet to see any reported issue with transmission on any 2019 and up.
There are thousands of these trucks on the road being abused and some are not and there is no official report of any failure ( as far as I know ) nor any complaint reported.
what we know is an oil analysis report on an abused truck at 50k came clean with no issue , today another at 300k hauling and towing again with no issues.
Unless someone comes forward and show us that he has a fried transmission, we can keep making assumptions as much as we want.

If an external transmission Cooler makes you feel better , sure go for it , it is your truck and I would do the same if I was that worried about the reported temp.

 

I agree 100% .

 

True , that many miles don’t see any down time for any maintenance being a 19,

 

I was going to write a lot more, but @blanchard7684 just dropped the knowledge so I'll just say this.
They would not have removed it just for savings if the engineers said it wouldn't work. Toyota is not NASA.

 

I'm not taking any chances. I've decided to cover my truck with bubble wrap and leave it in the garage until we figure this out..

 

That’s a lot to read but thank you! Perfect. Now try to explain where the heat goes from adding a cooler in front of the ac condenser, and mounting an aluminum cooler to stainless steel bracket with stainless steel hardware might be bad.

 

Maybe I missed it on the previous pages, but what truck is @Berettafan driving now?

 

galvanic corrosion. Surface area differences can accelerate this.

the heat load goes to 1) atmosphere 2) condenser and 3) the radiator/ cooling system.

 

Btw thanks for your contributions on this. Posting the hot lock up schedule starting (!!!) at 265F was a huuuge clue in all this stuff.

 

Thanks for the post. I fully agree that the Tundra is the baddest ass half ton out there. And I appreciate the insight into how Toyota might have come to the conclusion to delete the cooler.

By the way, I don’t think it’s luck that one guy’s truck went 300k with no aux cooler. To me, it seems more likely (there’s that word again) that Toyota decided it was overbuilt enough to begin with to no longer need the cooler.

But then, what to do about the 2019+ trucks showing trans temp warnings under normal working conditions? One guy got Toyota to fix it under warranty by—you guessed it—adding an aux transmission cooler!

 

Who got it fixed under warranty by adding an aux transmission cooler?

 

Who is the guy ? Is he on this forum ? Also what is normal driving conditions?
I tow 4K lb with my 19 and never had an issue ...

 

There are some very high temps in these transmissions however when you dive deeper you’ll see comments like “yeah I was doing 80mph in the mountains and she felt great with my 9k travel trailer.” That type of driving is going to cause excess heat regardless for ANY truck, transmission cooler installed or not. Higher speeds equals more heat and heat deteriorates...tires, engines, transmissions, axles, fluids, etc etc.

And why should Toyota test their vehicles at the UNSAFE speeds that many people tow these days?.?. I would expect them to test their vehicles at what they recommend in their manuals. Just because the truck can haul ass with a lot of weight doesn’t mean that you should. Slowwww down and I am sure those temps will drop significantly...

Terndrerrr I am not implying you drive fast or unsafe. I am generalizing comments I have seen in connection with the higher transmission temp topics.

 

Agreed. The manual clearly says not to exceed 60 mph when towing. I'm not sure anyone anywhere in the US drives that speed or slower.

 

Lol that is speed i cruise at get to the same place 5 mins later that if u are hammer down

 

https://m.youtube.com/watch?v=I8upLk9jlcQ

 

'used for towing and hauling' on that 300k truck is meaningless. like me saying 'i work out'.

used the new sequoia for a dump run this weekend. 5x10 utility trailer with 300lbs of junk in it. yep i towed with it. but we all know that ain't towing. yet i can say i towed with it.

 

I get the same temps towing 4K lb travel trailer or not ( of course towing per the manual) . So regardless of this guy towing or not , the fact that he reached 300k with a 19 speaks volumes .
Lot of assumptions over here that transmission on 19 and up would fail at 150k or so .....

 

I’ll second that... let’s assume the truck was put into service in August, 2018 so it’s been on the road for 30 months. That’s average of 10,000 miles a month and 330 miles a day - every day.

That’s a lot of effin’ miles...and gas! Let’s head on over to “what kind of gas mileage do you get?” Thread...bring your green hat!

 

Seems like people get upset over how others spend their money. Needed or not, if you put flame decals down the side of your truck, it’s your money and your truck.

$1000 for a trans cooler. People easily spend 2x-5x that much on suspension. Isn’t that a waste of money because Toyota engineers knew what they were doing when they picked the stock suspension and it’ll last 300k?

Yeah not everyone changes their suspension. But not everyone is adding a trans cooler either. The engineers knew what they were doing when they discontinued the TRD SC, but some people are still adding SCs.

 

I'm not sure you should be so rash until the internet engineers weigh in on the proper application of bubble wrap.

 

The above is a Toyota engineer (NOT acting in a PR capacity) who “deals with this [trans cooler] directly” quoted with permission. This seals the deal for me, Blanchard’s long hypothetical post notwithstanding.

People are fallible. Sometimes, even Toyota engineers.

I will try to find the guy who had the dealership install the trans cooler kit...If I recall correctly, it was the guy who got trans temp warnings on his 2020 using it the same way he used his 2017. I don’t recall finding it on the forum...I spent a long time reading articles and watching YouTube vids last night and closed a bunch of tabs.

 

It's ok, your GM doesn't have the same recommendation as far as I know.