TRANSMISSION . Transmission coolers for all Toyotas ... Write up with many pictures

Whoops, missed that while reading the first post.

Hmm, on further thought it's probably overkill unless the truck has had a lot of HP added through super or turbo-charging etc.

Towing a heavy load on a stock engine will probably make for a hotter manual transmission, but I'm guessing (?) not excessively hot, because the amt. of power dissipated through the trans can never be higher than what the stock engine puts out.

 

https://www.tacomaworld.com/threads...-oil-cooler-install-on-2nd-gen-tacoma.743299/

I did it with the driftmotion kit @gearcruncher mentioned.

Coming up on two years with it installed now.

In my personal experience monitoring temps over the past 3 years, including the year prior to install, the manual transmission on my truck does fine maintaining below 200 degrees on its own with ambient temps below 85-90 degrees around town and on the highway. Above 85-90 ambient temps, carrying weight, especially through the mountains, I consistently saw temps 200-220, but for the most part it maintained 210 or below. I did manage reach over 240 on one of my trips through the rockies when I was really hammering down and pushing to see how hot it could get.

I dont think a manual trans cooler is necessary most people, and driving style factors in, but if you tow really heavy loads through the mountains for long periods of time, i can pretty much gaurantee your trans is probably seeing 220 plus degrees for parts of the trip.

Happy to share lessons learned. I will be making changes to my setup so it runs of the thermostat as intended and not a switch, as I have it now.

 

Thanks for sharing, I was wondering exactly that, whether anyone out there had taken the time to do empirical measurements on manual-trans heat in different load conditions. Sounds like the stock manual trans is fine for 98% of normal Tacoma use cases, but for those who want to push the upper 2% towing a lot of weight up long grades, a manual-trans cooler setup could be useful.

 

Yep, agree with what you said about 98% of folks not needing it. I'll talk you into taking breaks before I say go put in a cooler. Install sensors before you dive down the cooler path so you know when you need to take those breaks.

Yes, mine has been on a manual switch because i am getting a much lower temp reading off my thermostat (180 degree trigger) with all the fittings and adapters I used coming off the trans because i didnt want to drill a hole. To deal with it I bypassed the thermostat for now with the switch, and just kinda know when i need to turn it on based on the gauge reading. Once i flip the switch and the oil is flowing my gauge reads fine. I usually flip it on when i see 120, it jumps from 120 to 200 as it gets the temp, and slowly drops down to 180 as it cools and I kill it.

An always on situation would absolutely create an overcooling situation. If I leave it on too long as I am coasting down hills or cruising into town temps will drop below 140. I have not needed to touch that switch even once in fall and winter as it gets cooler, even on those long trips through the mountains ambient temps do the job.

 

Sorry, I edited my post & removed the question about the ON/OFF switch etc. I noticed the link to your full build thread & went and deep-dove that instead. While there's no question that as a matter of basic principle, keeping a manual trans closer to 175-190º is a lot better than keeping it at 240º to 250ºF, I have more research ahead of me to determine what the safe / acceptable operating ranges are for high-quality synthetic gear oils. Not sure yet but my preliminary take (based on casual googling etc.) is that the higher-spec'ed ones may be fine up in the 260-280ºF range and even beyond. Don't quote me on that. I don't mean to suggest that operating in that temp regime regularly is a good idea, but if it turns out to be true then it gives a lot more margin for occasional extended high-temperature excursions, compared to automatic transmissions.

 

Ignorance is bliss. If you want another thing to worry about, put in a drain sensor and a gauge and monitor it so you can pull over when it gets hot.

If I am right about what the lines mean on my gauges then I never saw temps as high as 250, Def not 280, and to your point i agree its not the end of the world if you run at higher temps for a shorter period of time. I think the idiot light comes on at 300, but don't quote me on that.

 

I don't mean to spread misinfo re: gear oil (vs. engine or automatic transmission) operating temperature ranges. I'm really not sure yet. I'll need to do at least a few hours of careful deep-dive to figure out if synthetic gear oils in a manual transmission really can safely run quite a bit hotter than ATF can in automatic transmissions.

In any case, I would definitely start by just installing an accurate, well-placed temp gauge on the transmission to monitor my own real-world manual trans temps for some period before investing the time / $$$ / complexity in an outboard circulating cooler.

 

@gearcruncher
@SR-71A

Thanks for the replies gentlemen. Little peace of
Mind too.

 

Can anybody please tell me which is the return line and which is the send line on 3rd gen with tow package? I keep reading that you should install the hot line at the bottom line of the transmission cooler and let the fluid flow upstream rather than down stream. Here is a picture of how I’m currently running mine. Please @gearcruncher or somebody with this knowledge help me out here. Thanks! Lines are very short currently but I’ve made sure neither line will kink. bottom goes to bottom of cooler and top goes into the top

 

From what little I know and with help from the inner web this is how I understand the flow of trans fluid. ---deleted link------

EDIT
the link to the flow chart blows, so I deleted it and took a screen shot.


This is how my stock was and how my Long Tru-Cool LPD 4454 was installed. Check post #118 in this thread.




Also from what little I know, the 3rd gens need to "pin" something that controls the temp.

Hopes this helps

 

Thanks for sharing I can’t seem to get the link to work nor could I get the link in original post about fluid flow direction to open. Nice install you did btw

 

Awesome! I see it now! Thank you sir!

 

Here's another one for you.

 

If you have an IR gun, it may help determine the return line. On my oem 07, the oem trans cooler was installed on the return line out of the radiator.

 

I'm towing 5500lbs. Flushed Tranny and added a larger cooler. I'm in Texas and it's been a HELL of a summer. I've watched tranny temps climb just over 200 a number of times and I try to get it back below that. One time it hit 213 degrees. What is considered too hot for a 2nd gen (2015) automatic tranny?

 

Ideal ATF temp is 175-225.
https://www.motortrend.com/how-to/0811clt-tci-automotive-automatic-transmission-tips/

I have seen mine go up to 230 with an oem cooler. Last summer I replaced the oem with a slighty larger Hayden cooler and I immediately noticed average temps are 15-20 degrees cooler. In the hills, I rarely see temps go over 210, and when they do, they drop at a quick pace as soon as I hit the flats.

 

When adding an external atm cooler is adding a fan to it necessary? How close to the radiator should the cooler be?

 

It is not. The fan only come into play when you don't have good airflow, i.e. Low speed wheeling, stop an go traffic etc. Distance to the radiator is arbitrary as the don't work together. The cooler mount will typcally be straps that attach to convenient structure in front of the radiator. Most likely the cooler will end up an inch or so in front of the radiator.

 

Hey guys I've just released transmission cooler bracket kits available to order on my website. These have been extremely popular with the FJ and 4runner guys. Links below. If/When the OP thinks I'm worthy I would be thrilled to have the first post updated with a link to my website possibly.

I'm sorry I don't have better pics currently but these go on the passenger side and bolt in. I'm offering the first 3 people who send me/post good pics of the install to get $20 refunded from their order.

https://iconic-fabrication.myshopify.com/products/2005-2015-tacoma-transmission-cooler-bracket-kit
https://iconic-fabrication.myshopify.com/products/2016-2023-tacoma-transmission-cooler-bracket-kit

Pictured below is on a 3rd gen. 2nd gen is very similar. Totally bolt-in to existing holes, no holes to drill.

 

Those brackets look nice but $165 for the

$52 Hayden 678 Universal Rapid-Cool 9.5” x 11” Add-On Transmission Cooler – Not for Direct Replacement of the OE Cooler

Hayden 678 kit is pretty steep. I installed the larger 679 with no drilling. It was a tight fit and had to relocate a horn slightly, but no drilling was necessary. Did need a mending plate for one side of the cooler. Less than ten bucks, plus $48 for the cooler.