Better gas mileage with deckplate back on!

[tvpierce]

Tranny cooler tank is mounted on the SIDE of the radiator. Inlet is at the bottom, outlet at the top. The tank is part of the radiator, the antifreeze and transmission fluid are against the same inner wall of the radiator. If your antifreeze is at 200* your transmission fluid will be at the same temp. Do what you want with your own vehicle however an external cooler bypassing the OEM cooler is absolutely the most ideal situation.

You realize this is the 3rd Gen forum, right?

 

[2016 4Runner SR5]

You realize this is the 3rd Gen forum, right?

I do however there is certainly no harm is spreading proper information. Not to mention the 3rd gen is actually my favorite body style 4Runner other than the 1st gen of course. I do plan to grab a 3rd gen a build a solid axle off road monster in about a year. I'm moving next year about this time, don't want to have another vehicle to move.

 

[jgue467]

...
If your antifreeze is at 200* your transmission fluid will be at the same temp. Do what you want with your own vehicle however an external cooler bypassing the OEM cooler is absolutely the most ideal situation.

I agree with Phattyduck, radiator cooler plus external is the best - my experiences with only external, only radiator trans cooler and radiator trans cooler plus external show this overwhelmingly. Try driving your rig in central texas' 108 degree heat today! :cowboy:

 

[tvpierce]

I do however there is certainly no harm is spreading proper information. Not to mention the 3rd gen is actually my favorite body style 4Runner other than the 1st gen of course. I do plan to grab a 3rd gen a build a solid axle off road monster in about a year. I'm moving next year about this time, don't want to have another vehicle to move.

My point was that in the 3rd Gen, the radiator tanks are at the top and bottom, and the transmission cooler runs through the bottom tank.

 

[2016 4Runner SR5]

My point was that in the 3rd Gen, the radiator tanks are at the top and bottom, and the transmission cooler runs through the bottom tank.

OK good so I learned something. Doesn't change the fact that the tranny fluid is right next to the antifreeze in the same housing and there is absolutely heat transfer. The bottom of the radiator is the hottest part so tell me how that's a good thing? Antifreeze enters the radiator at the bottom and returns to the engine from the top. Top is cooler than the bottom naturally.

 

[tx_shooter]

I agree with Phattyduck, radiator cooler plus external is the best - my experiences with only external, only radiator trans cooler and radiator trans cooler plus external show this overwhelmingly. Try driving your rig in central texas' 108 degree heat today! :cowboy:

Exactly. I found my best solution to be running the trans lines through the radiatior cooler then to a temp switch that opens up as the temps come up sending the hot transmission fluid the external cooler. This setup has worked great for me for two years now on and off road. My transmission comes up to temp properly in the summer and winter, stays cool in town, and cools off fast after hard acceleration. The only thing I am doing to it now is to install a Transgo shift kit and new shift solenoids.

 

[AntleredRuin]

The factory trans cooler is at the BOTTOM of the radiator - where the coolant is cool. It keeps the fluid around 100*F above ambient (generally cooler than the engine coolant temp) except under extreme conditions.

I would love it if it were 60-75 outside right now.
It's high 90s in Houston currently.
I run an external cooler only for the past 2 years and have never seen tranny temps higher than 180. Sits around 160-175 all day long. Altitude and inclines have more of an effect on tranny temps than anything else.


Sent from my SM-G900V using Tapatalk

 

[tvpierce]

The bottom of the radiator is the hottest part so tell me how that's a good thing? Antifreeze enters the radiator at the bottom and returns to the engine from the top. Top is cooler than the bottom naturally.

?

I would be surprised if that's the case. In every vehicle I'm aware of, hot fluid is drawn in at the top of the radiator, and returns cooler out the bottom. Thereby utilizing the natural effect of convection to improve efficiency.

I can't think of any reason Toyota would deviate in this instance.

 

[phattyduck]

OK good so I learned something. Doesn't change the fact that the tranny fluid is right next to the antifreeze in the same housing and there is absolutely heat transfer. The bottom of the radiator is the hottest part so tell me how that's a good thing? Antifreeze enters the radiator at the bottom and returns to the engine from the top. Top is cooler than the bottom naturally.

Absolutely 100% incorrect. The bottom of the radiator is the outlet to the engine. The inlet from the engine is at the top. The water pump pulls coolant from the lowest point, where you are guaranteed to have coolant even if you are running low. This is true even on horizontal flow radiators unlike the vertical flow radiator of the 3rd gen.

Also, not 100% of the coolant flows through the radiator. If you engine is running at ~190*F (the correct temp for a 3rd gen 4Runner!), the bottom of the radiator will be much cooler than that in most situations. The temperature there is generally unregulated as it is the 'leftover' heat that the thermostat isn't recirculating in the engine (so, it will be much cooler there on a freezing day then say, a 100*F day). It is also the last place in the cooling system to get hot.

To top it off, liquid heat exchangers are much more efficient, so the small factory heat exchanger in the bottom tank does more than many aftermarket coolers.

Please don't spread misinformation. There is a wealth of knowledge here and many people with ACTUAL DATA from factory sensors via OBDII (including me) that can prove this is the case.

There are absolutely times where an aftermarket transmission cooler is needed, but it is also incorrect to say the factory cooler is worthless...

-Charlie