ATF Cooler on 2022 Tacoma?

When I was at IBM, I saw many poor engineering decisions made by Sales.
The ABit line of motherboards died in bankruptcy court when engineering decisions were made by bean counters to use cheap Chinese knock-off capacitors instead of quality Japanese components.

Anybody who doubts that engineering decisions are made by bean counters and/or Sales, is sadly naive.

Heat is the enemy of both electrical and mechanical parts.

 

Bean counters have been the death of quite a few businesses and organizations

 

This one is my personal favorite. Im planning of moving out of Ca maybe for good.Into a state that gets in the three digits during the summer.So this should do the job , also you can mount somewhere not visible

 

Theres a ton of info on this subject its been talked about for years click this link to read more...
https://www.tacomaworld.com/threads/transmission-temp-guage.498950/

On post #3 is the info, it also supports RIX TUX doctoral thesis lol

Also you can monitor it all you want but during the hot summers days it will be about 200f or more without a doubt unless you add an external aux cooler your truck is missing.

 

My main issue with these charts is that I can't find one that's not published by an ATF cooler manufacturer / seller. So a little too conflict-of-interesty for my tastes.

 

I didn't like the fact that the 2021TRDSport did not have an external Trans oil cooler. I added one.
I added a

$53 Hayden 678 Universal Rapid-Cool 9.5” x 11” Add-On Transmission Cooler – Not for Direct Replacement of the OE Cooler

Hayden 678 Trans oil Cooler to my 2021 TRD Sport.

I mounted it in front of the Radiator/AC Condenser cooler. It sits about 3” in front of those 2 coolers and about 3” behind the front grill. Big front nose on that truck - lots of room.

It is mounted on the drivers side as high up and to the right as (you face the truck from the front) much as possible , away from the front radar grill gizmo as comfortable, to keep it in the direct ram air inflow as I could. Moved horns to pass side.

I removed the original Bottom return hose from the radiator trans oil cooler and routed some

$23 Hayden 106 Transmission Oil Cooler Hose 3/8-IN Diameter x 4.5-FT Length

Hayden 106 trans hose from that port to the TOP inlet of the Hayden 678. Based on info from Hayden - a post, from Hayden reply:
From GPsevinSixx post # 103
.

Bottom return line from the Hayden External Cooler to original radiator return line connected with 3/8” id brass double barbed joiner. See below pic.. Obviously, kept the original hose connected to the tubing under the car, Didn’t touch that.



Hayden 678 Rapid – Cool cooler unit, with Hayden 106 hoses 3/8”, Fuel injection hose clamps from Harbor Freight. Hillman ¾”w/1/8”t/3’L aluminum stock for my homemade mounting braces. Misc warpy and external tooth lock washers, bolts and nuts with plastic inserts for locking. Black paint. Vise and hammer for persuading purposes.

Hoses covered in places with larger cooler hose for protection when threaded thru radiator wall and behind, where there is possible contact with other hoses. Paid attention to not KINK the hose at any spot. More than 4-5 in radius bend in rubber cooler lines for me. I blew through the whole set up, cooler and extra tubing, before final hook up to test resistance. Hardly anything felt.

PINNED the T-Stat. Added a quart of WS tested for leaks.

Entered in Oil temp Mode via great post of Post #517

https://www.tacomaworld.com/threads...smission-fluid-level-check-diy.547455/page-26

T-Stat PINNED, check bolt loosened-drained to a ‘dribble’. Maybe 10 oz came out. Additional oil of maybe 2/3 qt needed for the extra hoses and cooler. So, Trans fluid level/amount is accurate.

See below results with me in the PU with about 400 lbs of gear last month. T-Stat kept PINNED.

.

Its 95*F outside, Coolant is 190*F going 65 mph, with Trans oil temps are about 160*F. I can add 10*F by occluding the Hayden with a cardboard blocker and will do so for winter.

Done 5,000 miles ago . No troubles. Above results typical. In winter, I will put cardboard in front of about ½ the cooler and it seems to add 10* F.

I live in SE Arizona. We had 110 days of above 100*F this summer of 2024. Up to Grand Canyon, down to Puerto Penasco, Mexico: Some towing about 1500 lbs and some not. You can understand my concern about oil temps

Per post from Dbarffish at post # 449. If running through the radiator, when the trans fluid is cooler than the antifreeze, I’m sure the trans oil does get warmed up some. But look at the operating results shown above with trans oil routed through the Hayden.

Its is nice to have available, the extra cooling potential, when needed.

Looking at the results, I probably could have gotten along with a Hayden 677 considering my driving habits and lifestyle. Because of my cooler mounting location/method, I could keep the same hoses/lengths and just make another mounting brace and swap it out.

 

With a 40% cardboard occlusion in front of the

$53 Hayden 678 Universal Rapid-Cool 9.5” x 11” Add-On Transmission Cooler – Not for Direct Replacement of the OE Cooler

Hayden 678, temps raised about 10*F.
Notice the post above that at #66, the temp was 94*/F99*F but the trans oil temp was 158*F.
So, a 40% occlusion with a 20*F decrease, ( see below), in outside temp gives me almost the same cooling - or warming temp result.



Driving through Phoenix in June 2024, I-10 flat freeway, during the early afternoon, the outside ambient temp on the Tacoma dash read 106-108F*. Towing our pop up trailer, say no more than 2000lbs total, the tranny oil temp never reached 180F*. T-stat pinned, no occlusion. External cooler works for me.
Just reporting my experiences - you choose.

 

Here's the toastiest heat pic I could get. This is at rest, standing still.Temps are 8-10F* cooler when going 65mph.

T-Stat PINNED.
Here's the closest real time screen shot I could get. 203 miles driven, 3hrs 38min driving, at 106F outside, 203 coolant temp, with 173F in the PAN and 176F TC at about 1:23 PM. Car at freeway rest stop. Coolant seems to range between 185F and 205F on any one trip.