3rd gen Transmission Cooler Upgrade

The truck normally operates between 190-200 so I'd guess the oem thermostat on the sending unit opens around 190f. If your referring to a fan that's actuated by a thermal switch I'd say that would be too agressive and almost pointless since the fan would be on all of the time. It wouldn't provide any cooling benifit since the fluid thermostat will regulate the temp to close to 190 anyway.

I've been running mine pinned during the summer here in Phoenix. I may pull the pin when it cools off but I don't notice any Ill affects of having my trans fluid operating around the 160 range. Theres allot of debate about how hot is too hot for the WS atf. It's a reasonable thought that Toyota designed it that way to reduce friction and prevent sludge buildup but trans temps rising above 230 when the truck is working is also a legitimate concern. I've got about 44k miles on my truck. I run 35s metal bumpers and skids and also pull a trailer. As soon as I hit 60k I've having it flushed as preventative maintenance.

 

As far as bypassing the the radiator it's not a bad idea. My reason for keeping it that way was warranty. Even though I've got a bunch of mods I'd like to hope my powertrain warranty is still good.... all though the OVT FI kits are looking tempting lol. Hypothetically if my tranny gave out on me I could easily switch a couple trans cooler lines around and pull the big cooler on the side of the road before the tow truck shows up.

 

Of course if the dealer asked about tranmission modifications I wouldn't be dishonest. I just wouldn't divulge anything that's irrelevant to the situation.

 

You can do that if you run the thermostat pinned open. That way it would only turn on the fan when it gets above 190F and it will usually be lower than that

 

I'm going wheeling this weekend in the open desert. Going to spend most of our time underground but we have some sites to get to on old mine roads. I'll try and pin the thermostat open and see what temps I see. I don't have a fan

 

This is what I'm running in my Camaro and it keeps trans temps cool even with a 9" 4500 stall converter and transbrake

https://www.jegs.com/i/B-M/130/70274/10002/-1

 

Gotcha, I may do that. I'll have to remove it in the winter here in WI.

 

I haven't had time to read through the whole thread... did you mount the trans cooler in front of the AC condenser? If so do you notice any degradation in AC performance?

 

This truck has a huge condesnor! I've driven in 115F sitting in traffic and it never warms up. No worries there

 

TRU-COOL 4590 INSTALL - sort of: Got my Tru-Cool last week and waited until my SG2 came so I could check transmission fluid level after a full flush and fill. Flush and fill went okay - except the WS bolt was torqued by a 600lb monkey at the dealer when they did the initial low level check (3/4 qt low from the factory = tow package cooler and not pinning thermo). So after busting my hand it came loose. Drained the pan, replaced pan nut (properly torqued) and replaced volume of fluid drained, tightened WS bolt to proper torque. After 6 flush and equal fill runs the fluid coming out looked new. I was ready to add the .84 qts additional trans fluid to equal the volume of the 4590. Done. Hook up the supply and return hoses, tighten everything up and start the engine. WTF! the TRU-COOL is pissing fluid from its core. Mother of Mary. Kill me now. What a mess. Went to local parts store and got a

$58 Hayden 679 Universal 11” Rapid-Cool Add-On Transmission Cooler to Enhance Cooling (not for direct replacement of the factory unit)

Hayden 679. Installed, connected hoses, tighten it all up. Start engine....Yes! Success. Still have to do final fluid level check but that will wait until tomorrow. Enough for today. Moral to the story....TRU-COOL was a POS. Never buy from anywhere except the local parts store. My fleabay bay experience will find its way to the recycle bin.

EDIT: checked the trans. fluid level today. SG2 sure makes identifying the pan temp easy. Climbed under it before to be sure I could loosen the check plug. It was tightened by the same monkey that did the fill plug. Way too tight. Good news I got it loose and did not bust my knuckles! Up to temp and loosen plug - nothing comes out. Turn it off, pull front grill, take off return hose, pump in 1.5 qts, put all back together. Now its had an hour to cool because I decided to mow the lawn. Fire it up, check temp reached, pull check plug - out comes the extra fluid. Replace plug (torqued properly) when it is down to trickle and call it good. Ends up it was about 8 oz short. No way I lost that much fluid when the Tru-Cool took a dump and pissed its load - so even after Toyota added 3/4 qt (so they say) it was still short. Now I just want to drive!

@GmanCement18 Go to post #1 - good pics on entire process.

 

I am running thermostat sensor as I didn't wanted to add another switch in the cab and wanted to automate as much as possible. I got 180 F switch. Now, where you put that sensor will determine how often your fan comes on. I placed that sensor after factory tranny cooler and before new bigger tranny cooler with fan. Reason for doing so was fan wouldn't be on all the time during regular driving. Fan would only come on when small tranny cooler fails to cool down the fluid down (180 in this case). This usually happens when you are offroading at very low speed when your RPMs are low and clutch fan isn't spinning very fast and there isn't much air flowing throwing smaller tranny cooler. It has been working flawlessly as I desired.

 

Will watch the temps and see about the fan. Considering it is close to Fall, and my camping season is done if I do a fan it will not be until next tow season. May just pin it btwn June and September next season and then reevaluate.

 

Good thinking! I will probably do similar.

 

without the SG2 I never monitored my trans pan and converter temps. Went for a ride today but did not have the thermo pinned. both still went to 190. Went out for same later in the day and temps were about 150. Thinking I will leave it pinned until temps drop to below 40 for lows. ??? what have your temps been running - pinned and not. ??

 

Unpinned..145 to 184 so far

 

Not pined 190 pined 160

 

Help Can't find where this leak is comming from checked all the hoses and no sign of a leak at all.
Checked all the new hoses and nothing seems to be leaking. But what i did find was the front Radiator at the bottom that ruber gasket has wet marks all threw the bottom but mostly at the drivers side.
That rubber gasket at the bottom is the only sign i see where the oil is comming from.
Cant it be that radiator?? It is Trans Oil had my Mecanic install it. Im new to all this so i have no idea. Where else can i check

 

not the right thread for this, as it has nothing to do with upgrading to an aftermarket cooler.

Take it back to your mechanic since they did the work.

 

I did upgrade the Trans Cooler

 

i would take the factory hose clamps off and go with a worm gear hose clamp. Start there as that’s probably where your leak is.

Whenever you take the factory hose clamps loose, seems that sometimes they won’t get tight enough when putting them back on. Plus I like a worm clamp for any hose that is under pressure.