Install complete on additional transmission cooler

I finished the install of a

$216 B&M 70274 SuperCooler Black Aluminum Fluid Cooler

B&M 70274 transmission cooler, mounted in series with the stock cooler. I'm expecting temps drops in the 20-25 + degree range. The stock cooler alone could not keep up while towing, particularly in hot weather. I'm road testing today, unloaded. Towing the trailer on Monday if today goes well.

 

A long story really, but the readers digest version is.....New, unloaded, the tranny runs at 195-197*. This is by design by Toyota. If you pulled any grades, temps climbed up from there. Going over a 7% grade at 65 and 85* ambient, tranny temps climbed into the 220s. I tried pulling our travel trailer (6300 lbs gross) over the same grade at 60mph, at similar ambient temps and I had not gotten over a mile up the hill when temps had climbed to 240*, and I bailed out. I pinned the thermostat open, and that helped (the themostat doesn't open until temps north of 250+). Pulling the trailer on the same hill at mid 70s ambient, temps never got over 220s. But I was concerned what the temps would climb too in 100+ ambient temps. I had a

$216 B&M 70274 SuperCooler Black Aluminum Fluid Cooler

B&M 70274 cooler on my Tacoma and it did a good job of shedding a lot of heat. So I put that cooler in series with the stock cooler. I will be testing the new install today on the same grade.....I expect to not have a problem anymore, but I will post my results of today and of the trailer pull on Monday.

 

Thanks

 

Funny you ask. There is a fair amount of room, but I don't have a measurement right now. But you could put a fan on the front to blow through as there is still lots of room between the grille and the cooler. I may go that route if I find it is necessary for climbs that drag my speed down.

 

I'm going to be watching how this install affects, if any, the cooling of the motor/air conditioning. I don't expect a problem, but this is a bit of uncharted waters...

 

You should be fine. I have a b&m trans cooler in my old 4Runner. I have it mounted the same way, in front of radiator and a/c coil. It works great, act still ice cold. Temps hit 120 in the summer here.

 

Wondered the same as well...

 

My guess is Scangauge or an Ultra Gauge, crazy they eliminated the Trans temp gauge. If you look at your window sticker it lists it as part of the tow pkg but yet we don't Have it. Trans temp gauge is a must and so Dumb of Toyota to of eliminated it, heck its the one gauge you can actually monitor as the trans fluid temps change upon conditions.

 

The results of yesterday's test went well. Previously, pulling a 7% grade at 65mph at the summit at 75* ambient temps, transmission fluid temp of 205 at the torque converter and 196 at the pan. Today, same grade, same speed, ambient temp of 75*, trans fluid at 166 at the TC and 147 at the pan. Not only are temps lower, but the temp differential from the TC to the pan is greater, which make sense. The test on Monday will be pulling the trailer. I'm guessing the difference will not be as remarkable, but very hopeful my trans temps while towing will be much better with the addition of this cooler.

For the most part the data above is comparing apples to apples. Same driver, being mindful to drive the same, etc. There is one difference in the two runs. When I added the additional cooler I also did a complete fluid change. The difference is likely to be insignificant, but I thought I would mention it.

Yes, I'm using a Scan Gauge II.

 

Looks really clean and am curious to see the loaded results.

Good to know others are like WTF having the tow pkg with no way to monitor temps...that's pretty lame.

 

No need to disable it...Colder ATF will have a nice effect on the transmission clutch packs making them last longer and less wear on the oil itself..

With the unit thermal controlled no need to disable it..

 

John, nice job with the cooler.

ColoradoTJ, John,

using scangauge2:
Thermostat in my car seems to open at about 200F. The highest temp (without towing) that I have ever observed was 214F at torque converter (TC) and only for a few seconds ... I haven't towed anything yet and don't have towing data.
Lately every time the TC temps get near 200F to 204F, I immediately see a big drop to mid 190's and then down to 186-189F which is the water temp (WTF) and we all know why - John explained that in other threads. I will collect more data regarding the 200F opening as I only collect data once in a while (like a check up) and have the scangauge disconnected most of the times. I don't like too much distraction while I am driving ...
As a matter of fact earlier today, going up a relatively steep hill in S3, I noticed the TF2 (TC temp) of 204F for a couple of seconds and TF1 (pan temp) was in low 180's and I was going about 30mph and could watch the gauges and once the TC hit 204F, it did an immediate nose dive to 194 and then very quickly to 186F which was the WTF (Water temp). Then started to climb up slowly but I was on flats by then and it never went over 192F. I have noticed the sudden drop from 200-204F to about 185F several times. The first time that I noticed the transition, I thought the scangauge has gone wild since TC temp was jumping all over the place (going to lower temps) and i think i reduced the sampling rate on my scangauge to allow the data to settle.
John knows much more about this stuff and I will try to collect more data. maybe the tech manual specifies the thermostat opening temps. Maybe Toyota changed the thermostat setting in different model years!? Maybe John has a bad thermostat I will try to catch the 204F thermostat opening again since I drive up the same hill every day.

Alloutdrs1,
Most temp gauges are dummy gauges and are not linear over all temp ranges. For instance they work fine from cold to "normal" operating range and they sit at the same spot for a wide range of temps (i see with my other car the engine water temp gauge sitting at same spot from 168F to 205F normal operating temp in that car is 188-194F ... and when the car is near overheating, it will jump to the next "high temp region" and maybe a warning light comes on. by the time it jumps up, you have missed the early "early warning" signs. I think that's why Toyota got rid of it and they may display a warning light or a buzzer or a message (like low fuel) or both a msg and a light. So i don't think u are missing much. My car doesn't have it either but I would have preferred a dummy gauge! at least u know when its cold.

ps.
I may leave scangauge on all the time and collect more data. The only thing is that i am paranoid and worried that it may interfere with the ECU and mess things up. There has been no report of it (with Tundras) as far as I know but I need to get confirmation from Toyota or scangauge or both that there is no way it can mess with the ECU. maybe accessing the odb-ii data was designed for parked cars and not while driving and when ECU is busy calculating engine & driving parameters, etc. ...
it has been on my to do list to contact Toyota regarding the usage of odb-ii readers while driving but I have a feeling they will give me a big NO NO!

 

With the addition of this newest cooler, I likely will unpin the thermostat. Running too cool is not good for one, condensation can build up in the tranny. But with that said, stacked plate coolers like the B&M have a natural thermostat effect by reducing flow when the fluid is cool. So we will see.

I posted elsewhere here on this forum a link to a download of a 2015 service manual. That is where I got the info on when the thermostat lifts. When I quoted the temp it was from memory, so NOT exact, but definitely in that range. The search function on the manual is not that great, so it is a bit laborious to get to the info you want with almost 13,000 pages, but I will find it and post a copy of the page from the manual that talks about when the thermostat lifts. Agreed, the temp is too hot. But even the low temp the fluid is kept at, 195-197* is too hot. But it is all done by toyota for the purpose of having a positive effect on the fuel mileage of this vehicle. Hot and thin fluid improves mileage. How much?? Can't be much I would think, but when your mileage is the worst of all the 1/2 ton pickups, you will try anything I guess.

 

So this is obviously for trucks without the tow package then right? Essentially u are copying the tow package cooler

 

So I still haven't found the page with the specific temp the thermostat lifts. If anyone on here has the service manual, it is in the area that shows a diagram of how the fluid flows through the thermostat when open and closed. It also talks about how the thermostat operates with a wax inside it and when the wax melts, it opens, etc. Goofy system it sounds like to me, but maybe not.

Colorado TJ here is a document I did find this morning from the manual that is for troubleshooting another issue, but it shows that the warning light (idiot light) for high tranny temps comes on at 302* and resets, goes off, at 275*. Anyone that knows automatic transmissions know that at 300* you have cooked your tranny. And even worse, Toyota thinks running at 275* is ok, as that is when the warning light clears. So I'm not surprised they don't have the thermostat open until 250ish. When I find the real data on what temp the thermostat lifts I will post.

I won't be testing the temps today as planned. Ambient temps are low today, only 70* right now, they were supposed to be in the low 80s. Also, we have pretty high winds and given the direction they will be head winds, so with those two conditions, I would be comparing apples to oranges. I may do it later in the week, but if not then we have a trip planned mid-May and I will report then.

 

I'm pretty sure that TechStream has a logging function, and it reads from the OBD connector. I would think that you're okay getting data from there with the ScanGauge, unless SG says otherwise.

 

Got ya didn't know they had that type of gauge previously, I was thinking more of what my 14' silverado had which was a digital read out of the trans temp in the DIC display. That one you could actually monitor Temps while you were towing.

 

digital read out would be the best

John, the wax thing is interesting! does the wax melt at the same temp over its life time? how can you do a quality control on wax and have the same consistency on different cars? maybe in my car the wax melts at 200F
I am now curious that maybe my scan gauge code is in error. I copied it from another thread. If the 250F thermostat opening (wax melting) is correct then my scan gauge data does not make sense.

Have you ever noticed with scangauge a big temp drop when the TC temp reaches 250F like mine does at 204F (see above)? maybe I need to tweak my code since the trans temps needs to be hand programmed and are not available like water temp (WTF) and volts, etc.
Just realized that u may have never seen 250F since its too high of temp.
we may have to compare code at some point assuming its the same code for both models!

 

In general, if towing a lot in hot weathers, you should change the trans fluid more frequently.

I did a little research and found this on a chevy site and copied it below.
interesting read since it kind of matches the warning light trigger temp that John has posted from one of the Toyota manuals:
"Toyota thinks running at 275* is ok, as that is when the warning light clears ..."

From chevy site:
Maximum transmission temperature

In the February 2011 issue of Trailer Life magazine RV Clinic in response to a reader about the maximum transmission temperature allowed in a 2009 Chevy Silverado, the Tech Team had this response.

“General Motors’ in-house towing team expert provided RV Clinic with this statement: The maximum allowable automatic transmission fluid temperature is dictated by the transmission oil itself. The oil begins to degrade significantly above 270 degrees Fahrenheit, so we design vehicles so that in all but the most extreme conditions, the fluid temperature in the transmission sump stays below 270 degrees F.

We allow for up to 285 degrees F in extreme conditions (i.e. towing a trailer with combination loaded at GCWR in Death Valley). But for customer usage anywhere else in the country, even at GCWR, transmission sump temperature should stay well below 270 degrees F. Above this point, certain internal components, such as seals, begin to disintegrate rather quickly. Although newer synthetic fluids can withstand higher temperatures we still recommend this (270F) as a maximum temperature. "

 

I've had mine up to 220 230... coolant temp was about 202 or so. I don't worry about it, service it regularly and I think the system will function as designed

 

Yeah, the wax thing is a first for me, like I said kind of goofy. I didn't bother to research it as I wasn't going to be using the thermostat, just pinning it open. I never saw a big temp drop like the thermostat opening like you mention. But I never let my tranny temps get that high. I did get to 240* with my first pull on a climb before I backed out. For what it's worth, my neighbor has a 2017 Tundra, same as my 2016. We put the scan gauge on his rig and did a test run, temps and behavior were the same between the two vehicles. Just a tid bit of extra info.