99RX300'd

I've read extensively about how important changing the transmission fluid is on these cars.

There seems to be a few theories going around which are quite confusing.
Let's try to clear this up with one post shall we.

Ok, so it is recommended that the trans fluid is changed every 15k on these vehicles,
Now.. I've heard some people say that only 5 quarts are required when changing the fluid.
I was under the impression that the trans took 10quarts or more?

Some people stated that a flush is better, yet some say a flush is not because it may stir up debris into the valve body assembly.

The question is, when they say it is recommended to change the tranny fluid at 15k intervals, what do they mean, just 5quarts or?
Also, is there a filter that should be replaced at this time?

Lastly, heard talks of a clogged screen, is this supposed to be cleaned/replaced at the time of fluid change.

I apologize as I'm sure you guys have seen endless questions on this matter, I searched the forums and only got more confused

Anyway, thought some of the brains in here would have some insight.

Thanks very much

bob2200

I seem to be logging on right after your posts, so I'll take a stab at it.

My reading of all the postings is that drain-and-refill at 15k-mi is about the most aggressive position. I'm inclined to go with drain-and-refill at 20-30k-mi, as long as the fluid stays a bright red color. If starting from new (as I am), I don't see a flush or dropping of the pan in the future. (Another consideration is that I have a transmission cooler and I'm not hard on the car).

Note that many (maybe most) Lexus dealers don't even offer a flush.

If you're starting with off-color transmission fluid (as when buying a used vehicle), that's a whole different situation in my opinion. Then, the flush or don't flush options become a tough choice. My opinion (everybody is entitled to one) is to do maybe a half dozen drain-and-refills over a few months and then, when the fluid is back to bright red, go to the periodic drain-and-refills.

Tammy

All wheel drive needs five quarts (4.2) to refill what is drained from the pan and transaxle.
Front wheel drive needs four quarts (3.8) to refill what is drained from the pan and transaxle.
You don't drain the torque converter, so old fluid stays in the transmission and mixes with the new. This is the rest of the 9.5 quart (appx) dry capacity.

Whether you flush or the prefered drain and fills, is dependant on the current condiction of your fluid. It is not uncommon to drain and fill every 500 miles for a 1000-1500 mile interval to get the fluid mostly changed. But, if you want to do the job once, you risk doing a pressure flush. Just insure the flushing machine is filled with Toyota Type IV fluid and not something else.
The screen in the pan should not need cleaning or replacing, thus pan removal is optional.

Living in a warm climate, I drain my AWD transaxle a couple of times every ten thousand miles. Keeping the fluid fresh at five dollars a quart is much less expensive than a transmission rebuild.

But, if I used the RX for towing, off roading, hill climbing or hauling weight, the fluid discolor toward dark red would be my change frequency indicator.. whatever the milage. New Type IV fluid is a cherry red color.

TunedRX300

Lexus recommends only inspection of ATF every 60K under severe driving condition. 15K is recommendated by owners who have burned or black ATF before 60K. There is no external filter but it is not hard to install one by open up the tranny cooler return line and insert a Magnafine tranny filter.

I decide to go with Amsoil Synthetic ATF because my powertrain warranty expired, I figure by not using a superior fluid which can stands the heat generated by AWD tranny I am costing myself in the long run. I would rather buy a better product that can withstand a higher temperature and extend the drill and fill interval.

99RX300'd

Thanks for the replies.

I actually went to my local Lexus dealer and purchased 5 quarts of the trans fluid just to have on hand.
I asked if there was a filter that should be changed when doing the trans flush and he said no need...is that right?

HarrierAWD

Amsoil or any other ATF does not have the same viscosity and additive of genuine Toyota fluid. So soon you will experience rough/delay shift issue. After a while, your tranny will go toasty. So flush out the Amsoil and put Toyota fluid back in.

Lexmex

99RX300'd

What they are probably talking about is dropping the pan as opposed to just removing the drain plug and letting the fluid pour. By dropping the pan, once can see more of any metal filings that may have accumulated on the bottom of the pan but were not picked up on the drain plug's magnet. I would suggest that they drop the pan and let you know.

My two cents on the rest of the transmission fluid thingys:

1. I wouldn't do a flush if the fluid so brown or black.
2. Drain and fill about every 15 to 18K miles should do it. I generally would want to do drain and fill 3 times over the course of a month when that 15 to 18K mile mark hits.
3. Drain not only the transmission, but also the front differential, which also uses tranny fluid and by filling up your tranny, you are also filling up the front differential.
4. I might recommend a flush (one Lexus dealer in Naples, Fl did do a flush for me back in 2003) if you had silvery or pinkish fluid to rid the system of metal filings.
5. I currently use Type-IV, but I am also out of warranty and plan to switch to Amsoil ATF. I am a little more adventurous with my RX as you all know.

TunedRX300

I am not interested to start a debate or to join any side in this "Amsoil vs OEM" branding war. Just want to find out about facts:
1) Amsoil complies with T-IV spec. http://www.amsoil.com/StoreFront/atf.aspx
2)I also searched all Lexus models and so far has not found one owner who reported tranny failure by using Amsoil ATF.
3) I found also numerous cases of Toyota's ATF fall way short Lexus' own recommended change interal.
4) Toyota outsources to numerious suppliers to make T-IV ATF. Not surprising in this day of age. But this means Toyota ATF you drain and fill with could be made by a different supplier than RX's original fluid. At Lexus dealers, tech can start filling tranny with one supplier, ran out, then finish with another.

If there is no better reason other than "it is OEM", I am going to continue to use Amsoil.

Lexmex

Number 2 is the major reason I decided to switch to Amsoil ATF when I get back to the U.S. I can't get the stuff imported here on my own due to a hazardous materials license necessary for Mexico.

TunedRX300

Speaking of transmission, Toyota is already recalling early batch of 2007 Camry. My RX300 has 4 speed tranny, same as Camry's 6 speed - 2 gears

http://www.thecarconnection.com/Auto...73.A10341.html

Lexmex

I think it was an extremely small number of vehicles involved in this particular case. I like that Toyota got on top of this quick.

I got to test drive that new Camry today when I went to pick up some tranny fluid (going to do the front differential + tranny drain). This Camry has real improvement in the power department over the last Camry.

BTW, got my Royal Purple gear fluid, plan to change it out on Saturday (transfer case and rear differential).

HarrierAWD

There is good reason to use OEM or equivalent fluid. Each car maker has different viscosity on its tranny fluid. Without it, tranny will shift funny and in many cases, malfunction.

You could use non-Toyota fluid if it really matches Toyota Type IV spec exactly, but I have not seen any in the market place. For example, Quaker State makes a tranny fluid specific for Chrysler vehicles. Looking at Amsoil's spec with a LONG list of "compatible" fluids from different car makers, it is obviously BULL because no one fluid can match different viscosity requirement. It's physically impossible. Being synthetic does not make it better or indestructible.

Note that many Amsoil users are also its "independent distributors." Auto stores don't carry Amsoil for good reason. When something is sold through "pyramid scheme" or "multi-level marketing", you know you should steer away from it.

Just my 2 cents. Use whatever you are happy with.

TunedRX300

It is against the Federal law for Lexus or any automaker to honor warranty on the tranny on the condition
1) ATF must be Toyota or
2) service must be done at Toyota/Lexus

http://www.enjoythedrive.com/content/?id=8128

The Magnuson-Moss Warranty Act (15 U.S.C. 2302©)

I don't see Lexus giving out free T-IV during warranty period, this means there is other vendors that are T-IV spec complying in the market.

Harrier, what you posted is the concern most owners choose Toyota T-IV even though it is not cheap if you consider $ per tranny mile > that of Amsoil. But that concern is not valid as RX's tranny ATF is spec specific, not supplier specific. If it is the only fluid in the world to mainten RX's tranny, then Lexus has to provide it for free during warranty period.

Yes, Amsoil's one product supports many tranny but it does not automatically = BULL product for the RX. If one has fact, such as oil analysis result that indicates Amsoil's spec is nothing more than marketing, I am more than happy to learn.
Again not to debate but want to learn about facts.

ericok

The problem with the Magnuson-Moss Warranty Act (15 U.S.C. 2302©) is that if your get grief from your dealer for non-Lexus related warranty work, is that you'd have to sue to get satisfaction. Just pointing out this law to dealers doesn't seem to impress them or put fear in their hearts.

Lexmex

Side note, my father has a 1993 Mercedes 190E 2.6 and recently need some transmission work. I suggested to him that Amsoil would be an excellent replacement ATF. The first time he met the independent mechanic who was going to do his work, the guy was actually an Amsoil representative. Go figure.

Speaking of the Magnuson-Moss Warranty Act, Nissan USA was giving my friend a hard time on her Murano transfer case issue. The Nissan dealers here did such an awful job (it was a comedy of errors...i.e., like steering wheel overly crooked, stereo not working, lights going out, etc.) My family and I fixed those things along with the transfer case. Now they are saying we should have had everything done as Nissan instead of my uncle's since the car was still under warranty if they want a refund. If Nissan had done the job right in the first place, she never would have had the issue. I know people who go in for a simple oil change down here and come out with only a car wash. My uncle and I are masters in detecting dealer fraud here.

My experiences with Lexus were always satisfactory, but that may not be the case for everyone.

I am all for people trying different fluids in their vehicles. I might be the first RX300 owner to use the Royal Purple in the transfer case and rear differential. We have several who have been using Mobil 1 gear oil, too. In addition, speaking of ATF, I know several people down here not too long ago who had diplomatically-plated Lexuses who were using Mobil 1 ATF, not Type-IV and no issues. Still, we must err on the side of caution.

However, TunedRX300 is correct that we haven't heard on this forum (and I certainly haven't heard elsewhere) of someone using Amsoil ATF in their RX300 and running into problems.