Opinion: Push or Pull Fan for Transmission Cooler

Under normal driving conditions, I'm fine. But once I hit the mountain trails, going slow and in 4WD, I see my temps get up to 230* (even with OD off and shifted to lower gears). That's the gauge I watch the most actually. I plan on putting a switch so I can work the fan manually at all times.

Last time out I was doing something new and my truck was sitting, not moving for periods of time over and over (I was cutting limbs and trees out of a trail). So it was getting pretty saturated with heat (just my opinion, no facts to back it up except my temp gauge).

Sounds like you have bypassed your stock radiator trans cooler. I believe anyone who pushes their rig hard (towing, wheeling, mountain driving) and has a bypassed system has to do something more to keep the trans temp down, like adding a fan or possibly adding a second external trans cooler. But, I'm wondering what your trans temps are like in winter, especially in Alaska? Trans fluid has an optimal operating range which is around 150-180 degrees. Just like running too hot isn't good, running too cool isn't great either.
 
But, I'm wondering what your trans temps are like in winter, especially in Alaska? Trans fluid has an optimal operating range which is around 150-180 degrees. Just like running too hot isn't good, running too cool isn't great either.

My cooler has the temp by-pass in it so it only flows through the fins once it reaches 180*. Winter temps is over the 150* mark once I drive for a bit.
 
Erm.?? Good thing this is not an air to air cooler.

You know what he means.

We were also talking about turbos and their intercoolers. They make air to air, and water to air... air to air gets heat soaked in times like stop and go traffic. Water to air was better to eliminate that. Same thing would happen to our transmission coolers. If there isn't air passing through it, there's no way to cool it.
 
My cooler has the temp by-pass in it so it only flows through the fins once it reaches 180*. Winter temps is over the 150* mark once I drive for a bit.

My B&M 70264 cooler supposedly has a viscosity type bypass that will direct more fluid through the cooling fin channels as the fluid temperature increases. I ran my cooler in-series with my radiator cooler though instead of bypassing. I was wondering what my trans temps would be like when I visited areas with freezing temps.

Even with my set-up and driving in sunny warm California it can take my trans a while to hit 150 degrees especially if I'm driving on the freeway with lots of air flow. I was thinking being in a much colder climate would have a big effect on the trans temperature but I guess I was wrong.
 
My B&M 70264 cooler supposedly has a viscosity type bypass that will direct more fluid through the cooling fin channels as the fluid temperature increases. I ran my cooler in-series with my radiator cooler though instead of bypassing. I was wondering what my trans temps would be like when I visited areas with freezing temps.

Even with my set-up and driving in sunny warm California it can take my trans a while to hit 150 degrees especially if I'm driving on the freeway with lots of air flow. I was thinking being in a much colder climate would have a big effect on the trans temperature but I guess I was wrong.

I totally bypassed my original cooler to eliminate the Strawberry Milkshake. I'm sure if I ran both, I would have cooler temps when playing hard, but didn't want to take the chance.
 
I have this setup to cool the AC condenser!

We used water sprayers on our turbo cars to cool the intercoolers. Worked pretty well at getting rid of that heat soak.[/QUOTE said:
Using it to cool the AC condenser! Inserted another washer motor into the existing washer bottle and running a line to two bottle spray nozzles!
 
Hey guys, (and Ladies) What's the general opinion (or based on facts) which would be better for mounting a fan on the external Tranny Cooler? A fan that's mounted on the front and pushes, or on the back and pulls? Does it really matter? I've read regarding other applications, one can be better then the other.... But what about us? Would it really matter?

Can I ask why you need one? What are your tranny temps?

My same question.

The cooler alone helps immensely. A fan on a tranny cooler is redundant, since it's sits right in front of the A/C condensor and air passes from the engine fan. I understand that you are trying to protect your transmission, but millions, literally millions, of these 4Runners do just fine without either a cooler or an extra fan. Save the money and buy some awesome camping gear or some accessories instead!

P.S. I have a cooler on my 4Runner because I am supercharged and the previous owner burnt his past transmission by never changing the fluid.
 
My same question.

The cooler alone helps immensely. A fan on a tranny cooler is redundant, since it's sits right in front of the A/C condensor and air passes from the engine fan. I understand that you are trying to protect your transmission, but millions, literally millions, of these 4Runners do just fine without either a cooler or an extra fan. Save the money and buy some awesome camping gear or some accessories instead!

P.S. I have a cooler on my 4Runner because I am supercharged and the previous owner burnt his past transmission by never changing the fluid.

I agree that the high majority of the 4runners on the road are running the stock set-up and doing just fine but the key here is the OP has bypassed his stock cooler and is now realizing that his trans temps are spiking under harsh driving conditions. It is for this reason why I chose to run my external cooler in-series with the radiator cooler to drop my temps a little when I'm driving in the mountains and hauling a bunch of gear. Recently, I bought an OBD II sensor reader and used the Torque Pro app to monitor my trans temp and seeing the temp hit 232 degrees on one long mountain road grade inspired me to install an external cooler.

The OP is trying to address the high temps he's seen and others with bypassed systems have successfully dropped their temps with an additional pusher fan. I think he's on the right track.
 
I agree that the high majority of the 4runners on the road are running the stock set-up and doing just fine but the key here is the OP has bypassed his stock cooler and is now realizing that his trans temps are spiking under harsh driving conditions. It is for this reason why I chose to run my external cooler in-series with the radiator cooler to drop my temps a little when I'm driving in the mountains and hauling a bunch of gear. Recently, I bought an OBD II sensor reader and used the Torque Pro app to monitor my trans temp and seeing the temp hit 232 degrees on one long mountain road grade inspired me to install an external cooler.

The OP is trying to address the high temps he's seen and others with bypassed systems have successfully dropped their temps with an additional pusher fan. I think he's on the right track.

Yeah the cooler makes sense, but adding a second fan on the cooler is what I think is not worth the effort. An external cooler will already do much better than using the stock one in the radiator.
 
Yeah the cooler makes sense, but adding a second fan on the cooler is what I think is not worth the effort. An external cooler will already do much better than using the stock one in the radiator.

I think there's many on this forum that would debate that statement including myself. I guess the thinking is since the external cooler is not bathed in the hot engine coolant like the stock trans cooler is, it does a better job of cooling the trans fluid? People with bypassed systems have seen some pretty high temps when pushing their rigs and I'm sure you would see similar temps when pushing your rig with the stock cooler too.

I have researched this subject quite a bit and I still can't say if one is conclusively better than the other when it comes to keeping trans temps down. This is why I chose to run an external cooler in-series to get the benefit of both for cooling and also keep my trans fluid at a better operating temperature when running in colder climates. The trans fluid will heat up quicker to a good operating temperature using the stock cooler - At least this is what myself and others believe and it does make sense.

Here's a thread i started which ultimately steered me towards the set-up I chose:
http://www.toyota-4runner.org/3rd-gen-t4rs/217667-trans-temps-bypassing-using-external-cooler.html

Here's another thread I started in regards to how the trans fluid temp will affect the life of the fluid:
http://www.toyota-4runner.org/3rd-g...sion-temperatures-how-relates-life-fluid.html
 
Copied from my build thread....

This was the original setup. Yes, the wiring is pretty messed up. That's from several small projects installed at different times. So it was time to clean that up some as well.
20160620_124159_zpswsys2mr8.jpg~original


First, I had to remove the cooler, and then my horns. Here they are moved and rewired.
20160620_133221_zpsed0uuuzo.jpg~original


Test fit of the cooler and the fan.
20160620_140615_zpsieltumbq.jpg~original


It all fits! Yes, I do have extra hose which isn't needed. I wasn't able to get the hose clamps off from the tranny. I didn't have any pliers long enough to get back that far. I could do it if my truck was lifted up and maybe the tire and skid plate was off, but that wasn't going to happen tonight. When that happens, I will get rid of the old hose, and run this new hose all the way back to the tranny lines.
20160620_181053_zpsvzk1wrbi.jpg~original


I will add another pic with the grill back on later... Some reason I forgot to take one with it all put back together.

Second phase will be this:
https://www.amazon.com/dp/B00Z23HE7W/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=1GR0NNX7KNPQE&coliid=IYWRY4HPI4OGW&psc=1

I will be installing to measure both temps before and after the cooling system. That way I can document temps when cold, up to temp, and with the fan on or off...

Right now, I have just a temporary switch to run the fan. It's time to get a switch bank and relay mount to clean up my wiring. I'll pick those up and continue this. I'll keep this updated as I move along.
 
Let me know how it works out for you. I have a 70264 and still seeing over 200 on the street going up long hills. Contemplating adding a fan or a bigger 4589 cooler.
 
I have a 70264 and still seeing over 200 on the street going up long hills

Are you bypassed or in series?

NVM, you're bypassed, which might be why it's "spiking" like Tim mentioned... After reading some other threads, I've decided to add my trans cooler BEFORE the radiator, hopefully this weekend coming up.
 
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Are you bypassed or in series?

NVM, you're bypassed, which might be why it's "spiking" like Tim mentioned... After reading some other threads, I've decided to add my trans cooler BEFORE the radiator, hopefully this weekend coming up.

Yup I'm bypass. May upgrade to a 4589 and see what happens.
 
Regarding the people who have them in series with the original cooler.... Aren't you worried about the milkshake? That was the original reason why people were putting on these coolers. When I first did mine, a Strawberry Milkshake thread was popping up every week over on Yotatech.

Have you guys changed out your radiators so you don't need to worry about it?
 
Yup I'm bypass. May upgrade to a 4589 and see what happens.

I think I had the 4589 originally. I did have the external bypass so it wasn't cooling already cool fluid. I didn't have anything to measure the temps back then so I don't know if it worked better or not. Amazon has it for almost $100!

I still have mine (not the bypass though. Gave it to a co-worker). If I could tell what model number it was I would sell it to you. I just don't want to sell you something it's not. Anyone know a good way to verify what kind it is? I think all I can see on it is patent numbers.
 
I think I had the 4589 originally. I did have the external bypass so it wasn't cooling already cool fluid. I didn't have anything to measure the temps back then so I don't know if it worked better or not. Amazon has it for almost $100!

I still have mine (not the bypass though. Gave it to a co-worker). If I could tell what model number it was I would sell it to you. I just don't want to sell you something it's not. Anyone know a good way to verify what kind it is? I think all I can see on it is patent numbers.

What cooler are you running with the fan on it. I wonder what if any the extra 7000btus will do with the bigger cooler.
 
What cooler are you running with the fan on it. I wonder what if any the extra 7000btus will do with the bigger cooler.

I think it's the B&M 70264. Don't bet your kid with that info though. But that looks and sounds right. I've had it or years. Again, I can't seem to see any model numbers on either of them.
 

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