richonline

Hello Buys,

With the famous transmission pan drop DIY on the front page, I finally decided to tackle this task. After I removed the plastic cover under the transmission, I could not find which one is the transmission cooler line (to pump some extra ATF out). I know it may sound silly for you guys, but it is the first time I deal with this job. The hoses on my car look different than what are shown in the DIY. The DIY picture shows the cooler line hose on the passenger side, but I didn't see the similar thing there. A little confused.

I took some pictures here, hope some of you guys can help me to pinpoint the correct cooler line which I should remove and pump some extra ATF out. Thank you so much. BTW, the 1st picture is on passenger side, the 2nd picture is on driver side.

varithms

It will be one of the hoses that also runs to the radiator or to the cooler in front of the passenger front tire.

richonline

Thanks varithms. Sorry to reply late, just back home. Want to be sure, the second pic I attached shows two hoses (both with the BLUE clamp), the left one goes to radiator (on the driver side fan area), the right hose also goes to radiator (passenger side fan area). Should I have to use the right side hose or doesn't matter?

richonline

I just read another trans fluid change DIY for RX330 and it was shown the trans cooler line on 330 is on opposite side compared to the 300. Maybe different model years for the 300 have different trans cooler line design/location? Can any of you guys help to clarify a little bit? Just don't want to damage this baby. Thanks a lot.

richonline

One pic from the 330 trans change DIY is attached.It shows the cooler line location on 330.

Lexmex

Tranny cooler on the RX330 is on the driver's side unlike the RX300 on the passenger side. There is no different design on any year of the RX300.

richonline

Thanks Lexmex. A few more pics from the passenger side. Still couldn't locate the cooler line hose showed in the DIY.

carguy07

Maybe you just have a cooler in the radiator tank instead of the external one?

Look through the slots in the wheel well and see if you have a cooler in there.

This thread shows some good pics.

https://www.clublexus.com/forums/rx-...sher-dead.html

TunedRX300

DIY is for AWD, FWD may not have an external tranny cooler. You can use any cooler line, just open the right one so it is easier to direct ATF to a catching pan.

richonline

Hi TunedRX300. I didn't find any external cooler around the passenger side tire well, so it seems the FWD doesnt has it as you said.

BTW, when you said 'open the right one so it is easier ...', did you mean to use the cooler line hose which is connected to the passenger side of the radiator (one of the two hose with blue clamp in the 2nd picture I attached) ?

TunedRX300

Usually tranny will have a pair of copper lines to circulate ATF around, whether it is to an external cooler or a full-flow filter. Rubber hoses are used whenever copper lines need to bent around corners. Clamps are used to secure a rubber hose to a copper line, they are marked blue to indicate ATF.

After locating these ATF lines on FWD, you need to figure which of the two pumps out old ATF from the tranny, so it is the equivalent of tranny-to-AWD-cooler-line that I showed.
I no longer have the shop manual so you may have to experienment around and post back on what you found.

richonline

TunedRX300, tks again for the words on tranny cooler which gives me a better image. I just drained the ATF without removing the cooler hose (The 300 or I cant wait). Will try to find the cooler hose in a few weeks.

Kevvo1

This is old but in case any wandering owners like me is searching:
I followed the DIY (meant for AWD) and got stuck near the end with the tranny cooler hose. I'm not sure about others but with mine, FWD DOES NOT HAVE EXTERNAL TRANNY COOLER; Instead there are 2 going in and out of radiator. I flipped a coin and disconnected the hose on the DRIVER SIDE. I know this was the CORRECT one because when I started the engine, 2 quarts old ATF fluid came out before seeing the new cherry red ATF

Drcoffee

In the picture above you can see bottom center there is a rusty 90* steel pipe fitting. That is the return line to the transmission fluid pan. Just follow that steel line to where it becomes a rubber hose to the radiator.

CHUWANT

This is how I found it, except it was angled bottom-forward for clearance (situated between the front-passenger fender well lining and the windshield washer reservoir/pump assembly).

In this picture, it is suspended perpendicularly to the floor and hanging on a broken-off bolt.

I will secure it properly, but is it normal for my 2003 RX300 AWD (bought used) to not utilize this cooler? I even had the tranny rebuilt 5000 miles ago so I’m confused if this is an oversight or more of an optional unused radiator?

I don’t know but way around well, but I’m trying to look at search results for pics and info

I don’t see any “loose” hoses or lines, that is to say there doesn’t appear to lines that were forgotten or neglected to reconnect

I’ll take some pics underneath and around where the above pictures from this thread are of but is this ok? And why wouldn’t they (revuilt tranny installers) run it through this cooler?



Empty rad with no lines connected on my AWD RX300