What am I looking at?

Hello all,

Late to the game, I recognize this has been spoken about a lot. Trying to get factual information.

I have a 2019 Tundra crewmax, with tow package, limited, 5.7 L v8.

I see two layers to the front intercooler and lines, is this a form of a intercooler transmission cooler?

What am I looking at here?

I plan to tow a lot, thank you for your time!

 

1. Engine radiator
2. A/c condenser
3. Your truck is not turbocharged, you do not have an intercooler.

 

So if I’m tracing the lines correctly, the transmission lines seem to line up with the engine radiator, meaning they are integrated now?

 

Last two pics are the power steering fluid cooler.

 

2019 does not have factory transmission cooler. Found that out when I bought my ‘21

 

After some research, seems like they tied it into the radiator and is a fluid to fluid cooler and warmer. I guess in 2019 they changed the shift points for the transmission to help it operate cooler.

per Toyota mechanic spoke with, if less then a 280 degrees, they are happy. Which is insane in my opinion.

the fluid they use now can handle up to that temp and the metals they used for transmission I guess changed some. All super weird. By changing the shift points it helped reduce heat in other areas of truck although I can’t find anything on it.

 

I may track mine and see what the values are.


Anyone know if a OBD scan II can do this?

 

yes

 

What is the name of that little gauge?

 

Thank you!


What typical temps do you see in a daily average?

 

Normally matched 193ish both TF1 and 2 straight and level while towing with a locked up torque convertor. I still see 230 TF2 at the top of our 8 mile uphill run from our campsite where TC won't lock up but pan temp is about 30-35 degrees cooler

 

Does this read pan temp or active in the line temp?

 

Not sure ... I assume pan temp and torque convertor discharge temp. When TC locks up TF2 cools to pan temp rapidly.

 

This is in line with what I'm seeing on my '19 with 5,500 lb. trailer behind me.

On the flats through the desert she settles in @ 205-210º towing @ 62-65 MPH.

Climbing grades it'll be in the 220-230º range, and I think the highest spike I've seen was 238º and that was pushing it hard up a particularly nasty grade coming up out of the desert on I-8 east at the Imperial County/San Diego County line.
Two lanes, steep and curvy, and if you get stuck behind someone struggling in the right lane you're done. You're never gonna' get in the left lane again.

The spikes cool off right away once cresting the climb.

For now I can live with monitoring temps and doing drain and fills on severe duty intervals every 30K

 

Or if you got the extra dough and don't mind using up a little bit more real estate on your dash, you can get the Scangauge III that will give you readings and then some

 

Thank you all, very helpful information!

 

Also helps to tow in S4 as per the manual to manage temps. Towing in the overdrive gears (5-6) heats up the trans quickly

 

Scangauge 3 here also... So, far it has provided a LOT of info that I probably did not WANT to know, but needed to know for the long term well-being of my '21.

Yes, as previously stated 5th and 6th are OD gears for our rigs. Something else to point out is that the torque converter will NOT lock up in 4th (only 5 or 6th) when the truck is in 'D'. However, the torque converter WILL lock up in 4th if the truck is in S4. Also, S4 is a the only 1:1 gear, which is why it pulls so nicely and tows much better in S4 than D or S5, S6... The reason that 4th won't lock (obviously programing shift points), but when the TQ would normally lock up due to conditions (parameters) the truck is also reaching parameters that trigger the upshift to 5th. So, again, use S4 when towing VERY liberally. Also, S4 will keep the truck from constantly gear hunting on any grade or inclinel especially when towing.

The OD gears are meant to reduce workload on the engine. However, the reduced engine workload is absorbed elsewhere (the transmission)!!!

Many running in S4 and towing at fwy speeds 60-65ish will say that they feel the engine is revving too high (2800-3k). Yeah, you will burn a LITTLE more fuel, but the sacrifice is to the transmission, which is quickly heating up. I read somewhere that you won't get a high temp warning light for your trans temp until it EXCEEDS 250. I've seen non-towing/unloaded temps at the converted EXCEED 230 degrees on a short steep paved incline (more than once) and pan temps in the mid 220s. Just slowing down from hwy speeds 55-60 to make a turn off the hwy, I normally will see converter temps pass 220 (pan temps 208-210), and I live in a place that doesn't exceed 75 degree temps for the highs in the summer. Sitting still in D will drive converter temps above 220 as well (such as in a drive through), shift to P while waiting and the temps immediately drop...

Short bursts of 4wd will quickly push temps higher and 4lo temps climb almost immediately...

Just for reference the truck only has about 21k miles on it.

It's amazing how the gauge and changed my perception of what my transmission is doing internally (temp wise) in my '21.

I'm runnng a '21 Pro (2nd Tundra) and have NOT towed w/it. I towed considerably w/my '08, and I did NOT monitor w/a gauge, but the gauge did confirm what I "felt" to be right in terms of using S4, etc. over D while towing... I'd be curious to see what the temps were while towing when I was doing it w/my '08, but I'd bet considerably lower....

So, what's my solution now that I have the info?? Aftermarket transmission cooler is going in. I've had the gauge for a few months, and it was enough for me to decide to install a cooler. So, parts are almost all here (just waiting on few small dealer extras) and I'll be looking to install in a few months.

Here's a video (it's dry AF), but 12 minutes of watching this will give you an incredible amount of knowledg of how our transmissions work and why the OD gears in our trucks generate SO much heat. This will also explain why S4 ideal for towing, and also a bit about the quality and durability of these transmissions.

https://youtu.be/YM40HOYtLNc

From there you must decide if you trust that the high temps we are seeing in our 19-21s, from lack of having an external cooler, will not cause the fluid to degrade to the point where you'll experience pre-mature failure of your transmission. Personally, I don't believe that with those types of temps our transmission fluids are going to be able to retain their protective properties throughout their intended service life, and if the fluid isn't doing it's job then it will be my transmission that suffers...

This is just my belief, based on my research and personal experience and observations of my own 2 Tundras.

Sorry for the blast of good and sometimes conflicting information. However, there's plenty of details and specifics about temps guys have seen, conditions, remedies taken, and before and after results, etc. of installing or not installing a 'kit'.

Crap ton of info in this thread about coolers for our '19-'21s...

https://www.tundras.com/threads/5-7l-transmission-cooler-kits.60550/

Another transmission cooler TO DO or NOT TO DO thread....

Transmission cooler or not Thread

 

Good post. My belief on whether one should be installed or not largely depends on driver behavior. I also monitored mine for a month or so and was surprised to see that I was in the mid 230's just driving unloaded in rush hour traffic. I tow enough and drive offroad a lot in 4WD that it just made more sense to me install a cooler and not be as worried about cooking the fluid.

There have been a couple of failed transmissions 2019+, whether that is related to temps is unclear, but at least one reported high temps. Overall though, it seems most driver behavior has been OK with the lack of a cooler, at least for now. Time will tell if longevity is decreased on the models without them.

 

Awesome information.


How often do you do a drain and fill of your ATF?


Also, what transmission cooler do you suggest installing?

 

Same guy who is responsible for Gen 3? Thanks, I'm glad I added coolers to both our Tundra and Sequoia.

 

What product did you use for a added cooler?

 

Toyota parts, Derale cooler, cut/welded my own bracket, Ravenol ATF.

https://www.tundras.com/threads/parts-list-for-adding-oem-trans-cooler-to-5-7l.125248/

 

Drain n fill every 60k, but my first one on the '21 will be right at 30k when I do the cooler install... I'll then do another one at 60k (unless the first drain and fill smells burnt or excessively dirty)... if the fluid seems degraded, then I'll do a second one fairly quick after the first to clear out the burnt up fluid.

Hayden or Setrab seem to be the most popular...

I have a Setrab w/custom bracket from someone on the forum and then a few OE parts to complete the list (T-stat assembly, hard lines, etc..)

Quite frankly, as others have pointed out... any quality cooler should do the job

 

Most readers will display "1" and "2" which is pan temp and at the converter temp respectively...

 

Heres another option...I got the veepeak Bluetooth obd scanner. Then used the fusion app with the toyota upgrades. All in for $45. You can see a bunch of parameters on your phone or head unit if you have android auto.

I don't need to monitor all the time so I'm happy with it.

The $100 in savings went to my budget to piece together my own cooler like the GCS. It was about $700 including the custom bracket. It can be done a cheaper if you use a different cooler and diy the bracket.