nuclearn8

Took the GX out this weekend, took the same route with same ambient 100 air temperature both days. 40 mile loop, 70% highway.

Saturday with thermostat pinned open pan highest temperature reached was 167 when i pulled back back in garage.

Today with thermostat not pinned, operating as designed, the pans highest temp was 194 and it got there half way thru the route while cruising on highway

Moral of the story is pinning the thermostat open slows the rate of AT fluid heating up. I have no doubt if a long enough trip, even with it pinned open, the fluid would have eventually reached 194 but it would have taken a lot longer...

cwalker022

After some effort, I found a transmission shop in Aurora CO that would install the AT cooler. A huge thank you to Acrad and others for the details! I had to order the parts. Transmission is running 20+ degrees cooler now while towing (I have not watched closely when not towing). When climbing I70 or going over mountain passes, prior to aux cooler, I would hit 256F then the transmission lock up engages and lowers the temp to low 240s. Who knows what temp would be without lock up. I’m now maxing at 240F on the passes. Towing on flat land, I was 215-220F, now I’m at 190-200F.

Can someone tell me how to pin the thermostat open? I would like to consider doing this before a long haul.

Acrad

I think we have a real picture of it around here somewhere but here is an example from the AT fluid drain/fill instructions. It is on the passenger side of AT pan. It depresses fairly easily and you can just use a heavier duty paper clip if you want.

cwalker022

Easy enough, thank you!

dereswyman

Just got my parts in and looking to get this installed over the weekend. I originally ordered my OEM AT cooler from Megazip but they are out of stock with no ETA from Toyota. They refunded me and communication was great. Shipping for the rest of my parts was under a week even with a holiday weekend in the US. I ended up ordering from eBay under the same OEM part number and was able to get one for the same price as Megazip but looks like they may be out of stock too. For the transmission fluid I decided to give the Idemitsu TLS-LV (WS spec) a try at $35 for five quarts on Amazon.

Usafandy

Great post everyone. Acrad, hoping you can help clear up some confusion for me. I saw another thread where you posted a video of the Kaon AT cooler (from Australia), and really liked how straightforward it was and used the factory bolt on points in front of the radiator. (https://www.kaon.com.au/transmission...rado-150-s~120). I ended up ordering and just arrived today.

However, in Kaon’s installation video, they say to install the short hose from the cooler to the TOP outlet of the radiator, and the long hose to the AT which the outlet the former top radiator hose leads to. You mentioned earlier to hook the cooler outlet to the LOWER outlet of the radiator. I should note that the Kaon video is of a Prada 150 and the radiator connection is on the right side (US passenger side).

Getting a bit mixed up with TOP vs LOWER radiator outlet, and which to connect the cooler to - any clarification? Thanks.

Acrad

- existing line from AT to radiator which attaches to top connection on radiator should stay in place

- bottom connection exiting radiator should goto to inlet on your external AT cooler

- outlet line of your external AT cooler should attach to the return line to transmission / this is line that lower connection on radiator used to attach to

Does this help?

AT fluid feed line -> Top Connection of Radiator -> Lower Connection on Radiator-> Inlet of AT Air Cooler -> Outlet of AT Air Cooler - > Return line to AT

Usafandy

Definitely - many thanks.

Jacket

Wow - this thread fell to page 3 - unprecedented. It's on the list for me this weekend.

klinquist

Parts ordered! Thanks everyone for the contributions. Looking forward to diving in.

SamLexRXGX

Dear friends,
Any dealer/mechanic who can install this oem transmission cooler in my GX 460, 2015 MY. I live in dallas fortworth area. I asked my local dealer, he said if the car doesnt come with the factory they dont install it.

Thanks,
Sam

nuclearn8

Happy to help answer questions, it's a straightforward install... all oem parts that literally bolt right up using oem instructions. Are you not comfortable or don't have the time?... I would offer to do it again but I loathe working on other people's cars... i don't mind mine oddly enough.
what dealer? Try calling around.... park place lexus in grapevine is great... their sales and service managers are into modifying GX's... (both drive them I'm pretty sure)

SamLexRXGX

I called Sewell dallas and they do not install. I am not very comfortable to install myself and do not want to make any prying marks on the front bumper removal etc. I will call parkplace and see how much they quote.

cwalker022

I doubt you find a dealer that will do it. I called multiple and none would touch it. I found a local transmission shop in Denver that installed it. I bought all the parts. Went smooth.

nuclearn8

Try Tandem in Alliance, north of fort worth. Great aftermarket yota shop. Theyll do it.