DIY Trans Cooler for ~$300

It can definitely get pretty cold here, I’m in the midcoast region but single digits do happen. That’s probably what I’ll do is an inline thermostat.

 

@Mdl do you happen to know what size thread was on the transmission?

 

Not offhand. Do you have the elbows? Some have also used AN fittings too.

 

@Jego do you have the transmission elbow fittings? Any chance you can check the thread pitch for him?

 

I still have to fab up a bracket but it's pretty light. I also used a Derale thermostat with a 160 degree pill in it. This is the improved racing one, fsm145.

 

Yes, will do in a few minutes...

 

Metric M14-1.5

 

I thought that. I'm hoping you didn't run to the store just for that. Thanks. Hopefully it helps him out.

 

That’s the plan to use AN lines.

 

Thank you good sir!

 

When I saw your post, was about to leave for dinner. It was just a quick stop at AutoZone on my way. Hope it helps.

 

You saved me from taking it apart! Haha

 

Some folks here and on other posts have asked about using @Jmunk 's transmission bracket on supercharged applications. I spoke with him through PM and decided to go ahead and order his kit to install on my Magnuson 2650 equipped 2021 Tundra. Had to make some minor tweaks, but all is good and it is doable with a couple changes mentioned below...

I ordered:
@Jmunk Bracket Kit with AN Fittings
Hayden 689 Transmission Cooler - Amazon
OEM Toyota Cooler Thermostat/Inlet&Outlet Hoses, and Hard Line kit - eBay
8X OEM Toyota Spring Clamps - Toyota Dealer Online
2X OEM Toyota 12mm Flange Bolts - Toyota Dealer Online
2qts OEM Toyota WS Transmission Fluid - Toyota Dealer Online
7ft of Gates 3/8" Transmission Cooler Hose - Oreilly Auto Parts

All the parts above ran just under $700, which is about 1/2 of the current pricing for the GCS kit currently offered. You could certainly make it all cheaper if you choose to skip the OEM hardlines, or even skip the thermostat and remove heat exchanger which allows 90 degree fitts to be installed straight to the transmission body.


From looking at his for sale post on Tundras.com and his installation PDF, I could see that the upper bracket mount was going to use the same hole as the magnusson intercooler bracket, but would not interfer with intercooler, itself, as it is setback quite a bit. I measured the thickness of the intercooler bracket at .125", so I ground down his spacer by .125" to come up with overall thickness of .25". See picture below of the spacer installed with magnusson bracket and his trans cooler bracket...


The second issue I ran into and did not realize until I removed the grille, was that the one of the lower mounting holes of his bracket was going to use the same oversized hole in the lower radiator suuport as the Magnuson intercooler bracket. I initially tried to just place his bracket on top of the intercooler bracket, but the placement dictated by the Magnusson bolt hole in lower bracket made it so that the other lower mounting bolt on transcooler bracket would not align with the threaded hole in the radiator support. There was not enough allowance in bolt holes to allow this to line up, even if I loosened everything. I noticed that with the lower bolt removed from the Magnusson bracket, it was still completelty rigid and did not flex or move, so I decided to just bend that lower mounting tab of the Magnuson bracket out of the way so I could mount Jmunk's bracket in that space. I might go back later and just cut that tab off, but it is not visible or hurting anything at the moment. Below picture shows the bracket tab bent out of the way ands trans cooler bracket mounted... In the future, I will most likely just cut the bracket off where I placed the solid red line...



The only other change I made from his PDF instructions was to cut the lower hose grommet hole higher on the plastic shroud. The suggested lower hole placement left a lot of strain on the the hose, so I moved it up and got a less strained routing of the 3/8" cooler hose. 2 pictures below show the original suggested hole and new higher hole. I later found out that he had mentioned in the sales post to use the hgiher hole location for optimal routing is using his AN Fittings... This has nothing to do with supercharged application




The only other issue I encountered that has nothing to do his kit or having a supercharger was that the Gates 3/8" transmisson cooler hose ID made it extremely difficult to install the hose on the OEM hardlines I installed. I lubed the nipples and ID of hose with ATF and even with that, I fought like hell to get those hoses on to the hardlines... He mentions somewhere that differnet brands of 3/8" hose will have slightly larger/smaller ID's and maybe it's pertaining to installing the hoses on the hardlines, but he uses Napa brand 3/8" transcooler line. I think even if you plan to run hose all the way back to the thermostat unit, this needs to be considered. I could see that the OEM short connector hoses (probably metric) has a slightly larger ID and they installed quite easily on to the hardlines on the other side, with a little trans fluid swabbed in the hose.

Below picture shows the cooler and bracket + hoses fully installed. Did a 5 hour drive after this installation and no issues...



Any questions, feel free to ask away...

Erik

 

This is exactly what I was looking for. I may just go with the GCS kit since is bolt on, I hope. This is a high risk job and I want to make sure it gets done right so paying the extra $$$ is worth it for me.

 

Just ordered my cooler, hose and the brick.

Need to find out who has the dfx for the bracket.

 

https://www.tundras.com/threads/transmission-cooler-bracket.136129/page-3#post-3572837
https://www.tundras.com/threads/transmission-cooler-bracket.136129/page-3#post-3575762

I ended up downloading this file since I found a good deal on a Setrab 920
If you need it converted into dxf or something else let me know

 

I’ve been eyeing this hose for a while now, and received a sample from the seller (he has thousands of feet). It’s high pressure, so bend radius is on the big side vs diameter, and fitting installation/insertion requires a little muscle to push in… but it’s tough stuff at a stoopid cheap price. Too bad it’s not NBR lined, or it would be great for fuel, too. Oil only for this stuff as it’s CM lined (chlorinated polyethylene rubber).

https://www.ebay.com/itm/1271962731...Iw524ILeb9ZkbEh5mPneodqaQA==|tkp:BFBMlqr5z5Rm

 

I was able to order the OEM transmission thermostat (part #32970-34030) from Fred Anderson Toyota for $158 with their 25% off sale. Toyota of Decatur is having the same 25% off sale with basically the same price.

I also ordered some of the oil line @Jowett linked. Too cheap to not try out.

 

Read thru the install instructions for the cooler you are getting - the most Effective way to mount is WITHOUT a bracket.

Why? Unless you plan on using a fan - the BEST way to mount is straight ONTO the AC condensor. The 2nd most effective is behind the radiator and the LEAST effective is ---- you guessed it - using a BRACKET to place it several inches in front of the AC condensor.

This method will Save you some $$$ and effort. Luck and enjoy the cooler times ahead.

 

I certainly don't disagree with that, but some of has have limited space in front of the radiator and condenser - from, for example, and intercooler. Toyota mounted their separate transmission cooler to the side of the AC condenser on 07-11ish trucks, the incorporated it in to the AC condenser itself. IIRC, it worked very well except at speeds below 15 MPH with high loads. But even then, it was still much more effective than no cooler at all.

I've also looked in to adding an aux fan on the cooler, which I think would be a great solution so long as it doesn't impede airflow at high speeds. I am curious to know if I the bracket really affects cooling, though. On the one hand it makes sense. On the other hand, it may simply serve to direct airflow?

 

Why is the bracket the least effective?

I have the @Jmunk bracket with the Hayden cooler and I haven’t gotten higher than 190 but typically 185 is my new norm. My normal temperatures prior were 217-220, empty. I understand that cooler is better to an extent. I would say that is pretty effective if asked.

Honestly I am just trying to understand the thought process.

FYI, I did read the directions that Hayden provided that talked about cooler placement…I just have a curious mind…

 

Its all about airflow.

Compared to the other 2 install places - the airflow (when vehicle is not moving) is the Least when cooler is placed on a bracket a few inches in front of condensor. In my experience - the most heat gain to a trans comes from repeated stop-go (in higher ambient heat like 90+) - I notice even when letting off the gas and coasting to a stop the fluid temps come up - so I like to make sure air is flowing at those lower travel speeds - right in front of AC condensor or behind the radiator will have the most airflow.

And then if the vehicle off-roads at low speeds for extended periods - some folks report higher than desired trans temps in these situations also.

Most coolers come with material to install right up against the condesor or radiator including little rubber pads to shield the condensor or radiator fins from any damage from vibrations. You are going to like the affect this has. Luck and enjoy.