Originally Posted by 4RunnerMexico

Alternator Brushes: If you're still running your OEM Denso and the bearings are good, this will save you a headache in 40-50k. Pulling the alternator out and replacing these during a timing belt really only adds about 15 minutes of your time. Just pull alt. and remove 3 8mm nuts on the back.

TOYOTA: 27370-20130

Originally Posted by 4RunnerAquasport

Well, the pic in my post is just my half ass rig that I installed with plumbing strap to fasten the fan in front of the cooler. It has been a solid mount though, and I beat this truck quite regularly. Here is the fan that fit my stock trans cooler:
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Derale makes good fans as well, I have one on my 5th gen:
Tornado
As far as control, you can either put in a temp sensor with an auto switch, that has to be plumbed somewhere into your trans fluid hose then it will turn on the fan at a preset temperature. Here is one example:
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or you can put in a manual switch and there may be more options I'm not aware of.

I never tow and only want the fan to run when the trans gets overly hot during off road sessions. I have the Bluetooth OBDII Android app Torque Pro to monitor the trans temperatures. I mainly need the fan when I'm having to go through heavy sand and there is not much air flow at the slow speeds typically found in this situation, but it raises your temps quick and they will stay there.
But I don't need the fan all the time, and didn't want the battery/Alt drain, so I opted to direct wire mine with a fuse straight to the battery and a switch inside the cab. The switch I used was a cheap push button that fits in our empty slots either on the dash or on the console.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Make sure if you go this route it isn't for a 5th gen as it's a different size.

The Auto switch will most likely be your best bet, given your driving/towing needs.
Oh and there are a few OBDII monitoring systems to consider for this task, which you have probably heard of, or are currently using. Stand alone units like Ultra Gauge have been around for awhile. There are several BT apps now but you'll have to research if they actually give you accurate trans temps.
Torque Pro has a couple quirks but it's worked pretty well and has customizable views and gauges, and it will read and clear DTCs. I put mine on an old tablet.

Here is the set up I settled on in my 5th gen with my tablet and Yaesu on an Arkon seat mount. I can navigate and do weather on it as well.

Originally Posted by Roamed YT

That's not a bad idea!

Mine is currently in pieces in the garage as it's a 3rd vehicle but typically when I do a Tbelt on a Toyota I do the belt, water pump, idler and tensioner pulleys, serp belt, plugs and replace the rad. Cam seals are dry so I'm not pulling them.

Y'know... while you're there. I'm currently doing a truck that has 256,000KM (160K miles) that had an original belt and water pump. The rad was leaking badly and the water pump has been weeping for quite some time. A bit of deferred maintenance but I seem to find them for decent prices.

Originally Posted by fulltimervexplorer

Awesome thanks for that info i think my best bet would be to have switch on mine and always run it while on the hwy and towing for long periods of time the cooler the temp stays the longer the trans will last. I need to get one of thpose obd2 blutooth readers to keep in my obd2 port so i can monotor things . So far i do not monitor any temps and have been doing this for 3 years now while towing long distances

Originally Posted by AuSeeker

If you put the pusher fan on a manual switch make sure you use a power source that is hot only when the ignition switch is on or your risk draining your battery if you wire it direct to the battery, etc. if you forget to turn off the fan when stopping for a while or parking it.

Originally Posted by fulltimervexplorer

Will do thanks for the info. Were did you wire yours into?

Originally Posted by AuSeeker

I don't have a pusher fan on my T4R, just didn't want you to end up with a dead battery out in the middle of nowhere.