3rd gen Transmission Cooler Upgrade

Can you give us a temp. while monitoring with a scangageII , for what is too low of for the fluid for continuous running so as to not harm the trans ?

 

There is no real thing as too low of a temp for trans fluid. When it is too cool (usually under 100F or so) the torque converter may not lock and the transmission may delay shifting to the higher gears in efforts to heat the trans fluid.

My 4R has no thermostat (just checked) and with the 2 coolers, im running around 130-150 depending on speed and load. No issues.

 

Been running the SGII and been up to around 192°F as I pull into work and that's after a short hop off the interstate. Most of my daily drive is interstate and it sits around 170-180 on the interstate, so I'm hoping for some lower temps from pinning mine open. Sitting in the garage it gets up to 170°F, so I know it's getting some heat from the coolant through the radiator. So, I'm not too worried about it NOT heating up and I'll post what I see tomorrow on my way into work.

 

I don't know if anyone is interested in these captures. This is from a 30 mile drive mostly on the freeway with no hills. I have a trailer towing package. Everything is as it came from the factory. I have picked certain PID's out. There are a lot of others if anyone is interested.



Zooming in on when there is an increase in No 2 Temperature (blue cursor). This is coming off of the freeway at a stop. Is increase in engine temperature the reason for the temperature increase in Temperature 2 or are there other variables?



Zoomed in when Transmission Temperature went down.



Temperature increase from Lock Up OFF?



I plan a short hill trip maybe tomorrow if anyone is interested.

 

Personally, I think the rise when you come off the freeway is due to the downshifting. I see the same when I get off the interstate.

This is really cool data!

I pinned my transmission cooler open last night and I saw a spike when I pulled into work at 163°F compared to 192°F yesterday, so I'm liking the cooler temperatures. I did not notice any difference in the shifting patterns, but then again, I'm mostly on the interstate for the majority of my commute. I wasn't looking too much at the SGII while driving, but the few times I glanced down, it was in the mid 150s.

The transmission fluid temperatures did not heat up as fast as before and I also noticed that my water temps were a few degrees cooler. Not sure if that was due to the trans oil cooler pulling some heat off or not, but was an interesting note.

 

Sort of... if the transmission fluid is cooler, when it goes through the radiator it's not going to radiate as much heat into your engine coolant.

Remember that the trans oil cooler is after the radiator loop, so it couldn't really be cooling the radiator very effectively.

What are you using to log this?

The thing I find most interesting is the engine coolant temps... the temp profile looks just like an electric fan setup cycling on and off, I had no idea clutch fans did the same sort of thing! That clutch engagement point must be pretty strong. I always thought it was more of a "slowly ramping up" sort of thing.

Also based on those temps being non-towing non-hill driving people can officially shove the "lifetime fluid" BS.

 

Snap-On Verus Pro

I believe it is the thermostat opening and closing.

The service manual documentation makes it appear that there is a ATF Thermal Degradation PID to assist in determining the fluid condition. I find no evidence of this on the scanner. This degradation PID may help in knowing when a fluid change is necessary

 

wow that's an expensive one! Nice, though!

My understanding of the tstat on coolant was that it pretty much opens and then is open for the rest of the trip. You see an initial spike, the tstat opens which causes a slump in temps, and then it stays open and your radiator fans are what moderate your temps. Tstats don't open and close quickly, if you've ever checked one by putting it in a pot of hot water.

At least, that's how it works on my Miata. Temp comes up to 180, tstat slowly pops open and you see a dip back down to about 160, then back up to 180 & from then on out it's up to the electric fans. Temp hits 205 and WHOOSH on come my upgraded spal fans and the temp drops precipitously back down to about 190 and the fan relays click off.

Probably a double ultra secret PID we'll have to capture and interrogate a dealer tech for.

 

They can tell me what they want... I'm probably still going to change my trans fluid at 50k anyway and put in Amsoil. Personal preference, but I want to get what's in there out after the issues w/ the low fluid.

 

We are ordering our trailer stuff right now with some rewards cards from our credit card company.

$52 Hayden 679 Universal 11” Rapid-Cool Add-On Transmission Cooler to Enhance Cooling (not for direct replacement of the factory unit)

Hayden 679, Hayden mounting kit, Wix magnetic inline filter, extra hose, and wide mouth fluid pump,

 

Do it.... do it now!!!! You will want some extra brackets though. Hayden and Derale has a kit with the hardware.

 

Extra beyond what fhe kit comes with?

It's all ordered. Coming tomorrow to Wednesday

 

Yes, it doesn't come with the hardware and straps. Perhaps it does on the 679 kit?

I believe I linked the

$19 Hayden 253 Metal Mounting Bracket Kit

Hayden 253 kit before. Comes with the insulated tube clamps. I got it at Pep boys for around $7 IIRC, which is cheaper than Amazon.

 

I ordered that, too.

 

So, did anyone every come up w/ anything to just get the stock cooler to open up at some lower temperature instead of the standard 190°F? I liked the actuator idea, but just wondering if there was something simpler like changing out the thermostat to another Toyota drop in replacement.

I loved having the lower temperatures on my transmission, but I do agree that I'd have to pull that when we get colder weather, so rather have a better option than pinning it.

 

I know this write up is for 3rd gens but I think I am going to do this to my trans on my 2nd gen. Out in Arizona this past weekend my trans hit 233 and the engine got up to 210. Hoping with the extra trans cooler it wil help keep the motor a little cooler. Might try to sneak an extra fan behind the hayden cooler to help with airflow. Thanks for the write up!

 

We've had a few towing trips now with the cooler setup and have noticed some consistencies.

When on the flats and cooler weather (ambient temp 85° and below) my temp never drops too much lower than 160°F. As seen in the pic Tf1 and Tf2 had the same exact readings for some time in the conditions described above. This info tells me the the torque converter is locked up here at 159°F.
Now, does the trans not fall far under 160° because the torque converter is being prevented from locking up by the ecm or because the of the viscosity bypass on the Hayden cooler

 

Does the Wix filter open up? I want to fill it during the install

 

if its like the magnefine i wouldn't open it.
It can be opened but i only do that when i inspect them after removal. I have to cut the label, unscrew the top etc.
if you want to fill i would suggest a good sized syringe.

 

Thanks. Do you just replace the filter as a whole unit? I thought it had a paper filter inside