Towing problems- No transmission cooler on 2020 TRD Pro

How fast were you driving, were the roads hilly, and what kind of trailer were you pulling?

 

I dunno... I have access to 4 pallets of copier paper and 58 toner cartridges.

 

Around 4k lbs (including trailer). Lets call it 4500. Steel deck dual axle car hauler.



75mph, very hilly roads.

 

I noticed on hilly sections the converter is unlocked way more than on flatter sections. Usually right when going up or going down.

it will resume lock up when truck is steady on incline or decline.

 

That definitely is a nice setup! Beautiful trucks! I don’t mean to be a d$&! but with that setup, speed, and those conditions I would argue that 266 is on par. Those trailers for whatever reason are like anchors. Or at least the few I’ve pulled…

 

Thanks! Crawler will be frame stretched 20" here shortly and the front will be linked before it cools down enough here in AZ to actually go wheeling again. That and all of our national forests are 100% closed until September anyway due to fires.

I think that on par for a vehicle without an external trans cooler is probably right. The issue is that 266 is just too hot for trans fluid without very frequent flushes. There is no doubt that the external cooler is necessary if you actually tow with the truck but like many people have said, the vast majority of Tundra owners are just driving to the mall and throwing their kid's football gear in the bed.

I think that an appropriate solution would have been to make the external trans cooler an option rather than eliminate it all together. It could have been port/dealer installed and would have kept the overall assembly line and production costs the same without making it impossible for those of us that actually use our trucks like......trucks......to install a cooler and maintain our factory warranty.

For me.....trading it in on a 3/4 ton or 1 ton when the lease is up.

 

Crazy idea here...if the cooler can go on...it can come off. It might be a PITA but if you need a new transmission or are having catastrophic transmission symptoms take off the cooler. If you go in for warranty work for anything other than the transmission or radiator I guarantee the Toyota tech knuckleheads would not even notice the cooler and even if they did if it wasn't directly related to what they were doing that day not care.

 

Nice!

 

This is why you heated up so badly. Drop the speed down 10 MPH. The manual on every 2019+ recommends not towing over 60 or 65 MPH.

 

They never listen!!!

 

Here is what it says in my 2020 manual

 

Did not get a chance to respond until now but that is my thoughts as well. IMHO if the Tundra is driven at that speed or less in severe conditions like mountains and high temps that it will be just fine without the cooler. Consistently above…than maybe you will need a cooler?

 

To be fair, that warning / tip was in the manual before they pulled the ATF cooler. From my 2017 manual -

 

Very true but I think that is in both manuals for good reason. That while towing the Tundra should not exceed 65 mph. User be warned in a sense…. Now if the transmission fails while strictly adhering to the manual than I feel there is a legitimate gripe with Toyota. It basically says what how the truck should be used in conjunction with the maintenance guide.

 

Bravo bravo!!!

 

OK. I read that differently. I read this to mean "use S4, not D, in order to maintain engine braking efficiency and charging system performance", i.e. not to say "use D unless you need engine braking or more charging performance".

 

Speaking of what does the OM say, the Tundra is designed primarily as a passenger and load-carrying vehicle. This is from the 2021 OM.

 

You and me both.

 

When do you guys use engine braking going 90 on freeway or use the engine instead of brakes down a hill?

 

This - but only if you call 8% grades a hill. Brakes pads and rotors don’t last long riding the brakes down a huge grade especially when towing a heavy load.

 

Black Boxes Matter

 

The box isn’t black, it just doesn’t reflect any light in the visible color spectrum.

 

Would have, but I was a sleep. Naps on days off are righteous!

I originally thought the same, but wound up being convinced otherwise. Might have been you, Chris, that convinced me. I'm old and forget, but I remember learning... I think.

 

Why dont you give them a call and find out for yourself?

 

So maybe I'll just shove it in D and t/h and let it rip. I was only using S4 because members that monitor temps reported lower temps when they went to S4. Back to trying to fry this thing.

 

I have a 2008 that I have towed many things many places. I never read any manual on how to drive it. Pulling heavy I start in S1 and shift manually burping the throttle to let it.
Don't lug the trans, using the proper RPM range of the beasty 5.7 takes the load off the trans. Same with our 4.7 2000. I would and still do manually shift it, it does not hurt them.
I will be honest without the cooler on the new 21 I feel I will be adding it. I prefer the cooler the 08 has. I too learned the hard way years ago,
4 banger automatic 4runner pulling a heavy boat into a strong wind in OD. Smoked it.