There is lots of disagreement here about changing the transmission fluid.

https://www.clublexus.com/forums/es-...-location.html

 

 

You can believe others that will post here that have ZERO transmission experience or someone that has worked for Lexus for 30 years and been trained by Lexus. My local Lexus Service manager when asked about transmission fluid changes for my ES300h refused to take my money. He said they can cause more harm than good. I will listen to him because he knows a lot more than anyone on this forum about the maintenance of Lexus's. He went to Detroit where the transmissions are made and ask the question what is the #1 cause for Lexus transmission failures. They told them putting in the wrong fluid and not getting the level exact. Both factors that are present in a transmission fluid change.
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On Point! Leave it factory sealed..

 

 

Many here like myself take it to our local Toyota dealership. The only maintenance they do for me is an oil change every 10,000 miles and a brake fluid change every 30,000 miles. I change the cabin and air filters which takes 5 minutes. The wiper refills take again about five minutes and bought on line.

 

Exactly!!!

 

There is no requirement and/or need for a transmission refill or service on this vehicle, I have been told as much by my Lexus service rep.

 

I am replying to this thread merely offering a different opinion, not trying to pretend to know more than others. Just giving information for those who are researching and trying to decide which way to go.

I have worked on cars (classic restorations and hot rods) for over 40 years. I have also worked on military aircraft for over 20 years. I have been through several schools to learn about oil analysis and to operate the spectrometric analysis equipment. I did oil analysis professionally for many years.

Under normal conditions (optimum) most fluids will maintain their lubricating properties for a very long time. The Lexus transmission is sealed, offering the best protection against contaminants.

The automatic transmission has a number of friction related parts which generate heat and debris. Over time, the fluids resistance to heat will break down. All of the moving parts inside the transmission are still wearing, although normally, but still adding debris to the fluid and still getting very hot.

There are small magnets in the bottom of the transmission pan to attract the metallic debris, but not all debris is ferrous (magnetic). This suspended debris can also reduce the sensitivity of electronic parts (solenoids etc.) inside the transmission, even causing premature failure.

Just because a fluid changes colors (gets darker), does not mean it is bad or has lost its properties. An odor is a better indicator than color sometimes. But how will you know if you never test it or change it?

Most people will sell, trade or turn in their vehicle before a transmission fluid loses its lubricating properties. That is great if that is their choice. No argument here.

I change the fluid in my transmissions for several reasons. Just throwing this out there for anyone "on the fence".

1. The only way I know for sure that my transmission fluid is good, without the expensive equipment, is to change it.
2. Temperature changes (external and internal) also induce contaminates, mainly moisture.
3. I have checked the trans fluid level on a few brand new vehicles over my career and found them low. This includes my wife's brand new Toyota 4-runner with a sealed transmission. I changed it at 25,000 miles and it was low from the factory.
4. Every transmission produces friction and heat. This alone will break down any fluid over time, even the advanced fluids of today. I am sure there are transmissions that have lasted 150 to 200 thousand miles without a fluid change, but how long would they last with fluid changes?
5. If a sealed transmission never needs a fluid change, then why is there a drain and fill plug?

For anyone interested, here is a link that explains the oil analysis process and the many ways a fluid can degrade. Maybe overkill, but very informative.

https://www.machinerylubrication.com...nalysis-report

Again, just throwing information out there in case it can benefit someone. Not trying to change anyone's mind.

 

Do a search on "change trans fluid ES 350" and you'll find scores of opinions and probably a hundred posts. This subject has been debated ad nauseam... No need for a new one at this point...

 

rmak, how would you go about changing the atf on a sealed trans?
Thanks.

 

Most Lexus/Toyota Dealers won't touch it.

Mine is a eCVT and I feel it doesn't need changing so I'm siding with the Manufacturer on this one. If it were a different transmission with gears like a 6 speed or 8 speed I may have a difference of opinion. But as I have said before, I changed the fluid on the CT200h at 100K and I won't do it on my ES300h or any Toyota/Lexus eCVTs in the future.

 

"Sealed" is a joke. Your U660E transmission has a 6mm hex head fluid drain plug built into the transmssion oil pan just like all other Toyota automatics since 1968 and a 24mm fluid refill plug built into the transmission oil case above the oil pan. First 3.25 minutes of this video shows you how to check the fluid level. That's the most important step to master. Then the next 4 minutes of the video shows you how to drain the 2.1 quarts out of the oil pan and refill through the refill plug if you want to:

 

Yep, it is not sealed.

I watched my mechanic doing this on my 2017 (15K miles on her) last week. Cost me 2 quarts of WS and $50 labor charge. I even watched him refilled the same amount of oil from what drained out (2 separate gallon milk jugs).

I figured what the hell, it is only $70 and I just wanted to see how dark the fluids are, not as bad as I thought and the car felt the same before/after the drained/refilled.