3rd gen Transmission Cooler Upgrade

Here’s what I recommend for an aftermarket fluid cooler.

The stacked plate models are 1.5 inches thick compared to most pics of .75 inch thick tube and fin coolers I’ve seen posted on TW.
The stacked plate coolers are a bit sturdier and have no thin fins to worry about bending or crushing as on tube and fin models.

The largest 11x11x1.5 inch Tru Cool model by Long Mfg. will fit on the Tacoma. Rated for an extra large vehicle up to 28,000 GVW, they cost less and are exactly the same as B&M Supercoolers on which Long Manufacturing is stamped.

You can find them on Amazon and eBay.

That should keep your Tacoma automatic transmission from overheating under all conditions while dissipating a lot of BTUs.

Here’s my install. Isolated with rubber pad and rubber washers and using some sturdy scrap aluminum strips in the garage for brackets. That can be purchased at HD or Lowe’s.

 

with how cheap they are now, theres really no reason for using a tube and fin cooler anymore unless your replacing an OEM part and thats a slick install, just needs a fan and its perfect

 

How about changing the trans fluid to Redline or Amsoil full synthetic? I bet you would see even lower temps especially when towing.

https://www.tacomaworld.com/threads...a-ws-atf-automaitc-transmission-fluid.373083/

 

I mounted with my inlet and outlet on top. The directions said to mount on top or on the side.

 

Third gen has a 195F thermostat. It won't matter what fluid you run if the thermostat doesn't open until 195

 

Just pin the thermostat and your cooler will work all the time. It helps a lot when towing!

 

I have a tranny skid plate and pinning it open is almost impossible lol

 

Nice bumper

 

https://www.tacomaworld.com/threads...ure-pids-for-torque-pro-and-now-apple.513531/

 

Need to check this thread out later. Nice work @Lord Humongous

 

Just curious how hot your trans is getting when you 4 wheeling?

 

Wow that's crazy. I wonder if the spending unit is going bad?

 

I removed my return line filter today. It was starting to weep on the input side and I assume it's clogging up after 20,000+ miles. I replaced it with a brass plumbing barb



Picture did not rotate correctly. It flows from passenger to driver side

 

I pinned my thermostat open today for the hot drive home into the wind. It towing around 165F when in 4th gear with the converter locked. Towed about 210F when pushing third gear going uphill and into a 40mph head wind at around 40-50mph. That's a 30 and 20 degree difference, respectively

 

I own the same Passport trailer 153. Will be towing it with my Gen 3 Taco in May. Curious to how your Taco does towing your Passport? Any issues with AT since you have been monitoring transmission temperature? Thank you !!

 

I had to unpin my thermostat when winter started. I fired up Torque Pro to check the transmission fluid temperature on a 60F day and the full heat temperature without towing on the highway was 130F. I'm not comfortable with that when Toyota wants it 195F

 

I’d say that you shouldn’t worry about fluid that at times is running at only 130 degrees.

It might be collecting additional condensation, but that can be remedied by an occasional long drive and/or changing your transmission fluid a bit sooner than recommended.

If a person does short daily commutes of just a few miles to work and back, which describes what a lot of people do in their trucks, the transmission temperature probably doesn’t get much higher than 130 degrees, and could possibly be cooler than that after just a couple of miles.

During a transmission level check, it took a few laps around the block on a warm day just to get close to 100 degrees at the transmission pan. Of course the converter is a bit warmer.

I’ve only driven in temperatures as low as just above 0 degrees. After letting a vehicle with an automatic transmission warm up for a few minutes before driving, I’ve never had an automatic transmission shift improperly in cold weather.

People in northern States and Alaska might have different experiences with cold transmissions in extremely low temperatures that they could share with us.

I have no idea why Toyota wants the transmission to be at 195 degrees or so. Perhaps it has to do with viscosity and lubrication for optimal operation.
But, again, there are many people who drive short commutes where the trans temp doesn’t get anywhere close to 195 degrees.

Are they having transmission failures of any kind due to cool fluid?

I’ve only often read and heard people say that you can’t overcool an automatic transmission.

I think it’s an interesting topic.

Perhaps some mechanics could give us some thoughts about it.


It seems that extreme heat is what kills transmissions, and it’s also what can shut your Tacoma down unexpectedly.

 

Lots of good advice in this thread. I've taken the advice of many here and pinned the transmission thermostat open, and can already see better temps. Now I'm waiting for a July day when it gets above 110 degrees outside to see just how much it can really help.

 

I towed my 4400 lb TT up a 6% grade at 88 degrees and the trans temp only got to 230 degree (scan gauge2). I had the trans thermo pinned. I'm hoping that means I don't have to add a second cooler to the transmission.

 

The important number would be TF1. TF2 is your torque converter reading. Unless your babying it TF2 is going to get up there on the big hills due to increased RPMs and the fact that the converter is unlocked. I've noticed 40+ degree differences between TF1 and TF2 with the secondary cooler and pinned thermostat. Once I back off on the throttle TF2 almost immediately cools to TF1 readings.