carguy75

The 3rd Gen Lexus RX350 transmission fluid change is a bit different since we do not have a transmission dipstick like the previous generations.

From what I read online and in the Lexus service manual, we have to used a special fill tool to pump the fluid into the transmission oil pan itself.

Furthermore, the transmission fluid has to be running at a certain temperature to allow the fluid to expand correctly to measure if the fluid level is correct or not since it stop flowing when it is correct out the drain hole, however if the temperature is not right too much fluid could drain out and cause issues later on.

This video explains the issue with our transmission.

Clutchless

I would not touch the filter, just do what I and many others have done, a cold drain and fill. You can drain about 2 quarts and then easily replace them through the fill hole on the side bolt inside the driver side wheel well. You remove a cover at the lower corner of the fender liner. Make sure the car and new replacement fluid are the same temperature because hot fluid expands. Then repeat the process 2 more times and you will have replaced. most of your fluid. Then I just do drain and fill with every oil change. The thread below has detailed instructions on the last couple pages.
https://www.clublexus.com/forums/rx-...hange-diy.html

carguy75

Thanks for the links, however the V6 Highlander in the thread uses a 5-speed automatic, so different transmission and procedure.


Some of the Highlander how-to threads are useful for the 2010-2015 RX like the spark plug change, however not the transmission unless the owner has the 2009-up 2.7 4 cylinder engine which does have the six-speed transmission.

Weird, but that what Toyota decided.

3.5 V6 gets 5 speed automatic until 2013 and the 2.7 4-banger gets the newer 6 speed automatic.

However, I do not know if the 2.7 Highlander 6-speed automatic transmission has a dipstick or not.

hovbuild

300 for a proper fluid drain or replace is not a lot of money if done as the video. thanks for posting and i would not let this be done unless as shown. and certainly not by me in my driveway.

Clutchless

Strange how Toyota assigned different transmissions to such similar vehicles with the same engine. I had a 2005 ES330 and I got rid of in 2008 because I hated that 5 speed automatic. The downshift delay when you needed to get onto a freeway was so long it was dangerous.

The clublexus link thread on drain and fill at about page 3 has a post by me where I attach a PDF of the drain and fill procedure we used on the MINI Cooper which has a similar Aisin 6 speed automatic with the same no dipstick, situation. It also has the overflow plug etc. However, on the RX the fill hole is much easier to access. The attached shows how much fluid is replaced after so many drain and fills.

carguy75

Toyota probably left the 5-speed in the 3.5 V6 Highlander to help sway more buyers towards the RX350.

Funny thing is that when the 2013 Highlander got the 6 speed, the RX gets the 8 speed transmission.

It is marketing game that works, because I was going to consider purchasing a 2011 Highlander V6 AWD until I found it had a 5 speed automatic and less gas mileage than the RX350.

Thanks again for the information because I will be doing a drain and fill soon on the RX350.

However, I will change the filter at 100k miles before it begins to clog/saturate with fine metal particles and start starving the transmission by reducing fluid flow which accelerate wear.

After the 100k miles fluid/oil change I will only change the filter/fluid again at 200k miles since the old transmission fluid from when the car was new has the most fine metal particles created during the break-in period when there was more metal to metal contact.

After the 100k mile filter/fluid change the fluid should remain fairly clean for the next 100k miles.

I was told this information by a friend who service transmissions, and he states that changing the original transmission fluid/filter early remove the fluid saturated with extra fine metal created during the break-in which will extend the life of an automatic since clog filters is what really kill a transmission due to reducing the fluid flow which allows the transmission to overheat and wear out it components as well as the solenoids.

Clutchless

If you install a Magnefine inline filter your pan filter will never get dirty. They easily fit in the transmission cooler hose. You just have to determine the flow direction. I have used them in several vehicles, they last about 15,000 to 30,000 miles and were used by Ford on replacement transmissions (that says something) Only laziness has stopped me from installing one on the RX as I have one in my garage!
http://magnefinefilters.com/?gclid=C...OvvhoCQMPw_wcB

fastnoypi

in your other vehicles with an installed Magnefine inline filter, are you still getting filings on the oem magnetic transmission drain plugs at drain intervals? While its a neat product, i wonder about any pressure differential the inline filter may cause.

carguy75

You are the man!!!

I may just install one of those inline filters when I do my drain and fill, and inspect the filter at 100k miles to see if i really do need to change the pan filter or not.

If the Magnefine filter catch a lot of particles then i would change the pan filter since it is most likely saturated, however if the Magnefine is fairly clean at 100k miles then i would just do another drain/fill and use the Magnefine filter again.

However, I still may just pulled the pan and change the out the filter at 100k miles due to the age of my transmission and also clean the sludge out of the pan/pan magnets.

The Magnefine filter would be a good preventive maintenance item for a newer RX or any car which would alleviate the need to change the filter/fluid until much later if at all.

carguy75

Good point.

Clutchless

I do not know as I never checked the pan filter at that high a mileage. The one time I did change it was years ago on my 1994 Mazda MX6 at around 50,000. It had a Magnefine and an additional trans cooler and Mobil 1 synthetic ATF. The pan filter looked very clean. There were filings on the pan magnets, but that was expected and had accumulated prior to installation of the Magnefine at about 30,000 miles. I sold it to a friend and it had no transmission problems when the head gasket blew at 140,000 miles.

However, pan filters are basically like window screens, they only catch the big bugs. Most of the comments and reviews at Amazon or other vehicle owner forums or www.bobistheoilguy.com highly praise the Magnefine for catching much of the debris that would be missed by a pan filter and reducing the wear cycle.
A Magnefine changed every 15,000 miles or so will keep everything very clean. You can take them apart after removal as the top comes off. I think they unscrew. When you buy one make sure it is the made in Australia real thing and not the Chinese copy that has had failures.

CookieRoe

Great thread! I've always been told that the ATF could NOT be changed. I know that is hogwash, but I did find that our transmissions are the U660F (link: https://en.wikipedia.org/wiki/Toyota...smission#U660F ). Anyway, I'll be taking my RX to the Toyota dealer to have it done as opposed to my Lexus dealer who tells me "Lexus doesn't recommend it and we can't do it". Ughhh

Thanks!

Zmon

iTrader: (2)

Just make sure whatever dealer you take it to has the machine that actually flushes it as not all of them do. When I brought my IS to my Lexus dealer, they got me for about $300, so expect to pay somewhere around that for your RX (luckily, I'm a long ways from needing that done on my RX). You can try and push them for a filter change as well, but they may not be interested in doing that.

CookieRoe

Oh yes, I"ll be sure of that. $300 sounds about right. About the method of doing it, I don't know of many dealerships that would only disconnect the in/out lines and do it that way (DIY), when they would/could have a machine that would do that. Our local Toyota dealer has such a machine. Our local Lexus dealer, according to the service manager, does NOT. It's funny when he tries to convince me that Lexus says it's a lifetime fluid. We had a 1991 LS400 that the transmission started dying due to no maintenance being performed on it. Poor thing had it's original ATF since new (at the time, it was 18 years old when it was traded in).

Anyway, I truly believe these fluids NEED to be changed regardless what the manufacture or dealer says. Unless of course I plan on getting rid of them and not caring, that's another story.

lexus114

same here. bennett toyota told me they will flush the trans as well.