I saw a video on a drain and fill but in the video he said to not do a drain and fill past 100k miles. One of the comments asked and he replied with

“You are on the borderline. So at 100k miles or more, it is not recommended to do a trans fluid drain and fill because in that old fluid, the metallic can be what is causing your transmission to not slip. However, If you do one drain and fill, you will still have old fluid in the system which will have metallic still so it would be okay. If I were in your situation, I would do 1 drain and fill and drive for 10k miles to see what it is like, then do another then monitor again to ensure you don't get transmission slippage.”


My RC has 90k miles on it right now, I looked at the service history and it had no signs of service on the transmission. Is it safe to do a complete flush with a filter and gasket replacement as well?

 

Only you can decide. You are going to get opinions for and against and everything in between.

 

Theres no way you can damage a mechanical assembly by replacing the old fluid with fresh, new fluid...assuming its the correct type. Change your fluid.

 

I flushed mine (and TVD diff fluid) at 100k. No difference in performance but most transmission issues stem from it not being warmed up.

 

Here is an ATF thread sticky form the ISF forums. Sometimes I refer to the guys who have been on the F platform the longest to weed through all the assumptions and such.

https://www.clublexus.com/forums/is-...tructions.html

 

There are a lot of opinions about this. As the fluid breaks down its wearing close to the same amount of wear on the clutch packs. The reduction in the fluids lubricating ability is helping the worn clutch plates still grab. Nice, new, slippery fluid can often expose worn parts because they don't grab as well as they did before. Hope that makes sense. Its a good idea to take a look at how a "wet clutch pack" works to better understand what's going on.
Here's my opinion. If you are not having any transmission problems you should do a multiple stage spill and fill swap of your trans oil. Any good technician will know how to do this. Basically you will have to go in twice over a few week period. It's when you drain half the liquid, fill and drive the car for a while and then do the same thing again, effectively changing most of the fluid but leaving a good enough amount of old fluid mixed in. You can do it a third time if you want to as well. You're easing new fluid into the system with the old fluid but in the end, you'll end up with fresher cleaner fluid with the lifespan of almost new fluid. I have been planing oil doing this to mine. Toyota trans fills are weird because you overfill them then run the car and let the overflow run out of the trans until it stops dripping and that's the fill line. You kind of need a lift for that and the nearest Lexus dealer is a hour away from me.
If you are having any trans slippage you better leave the fluid alone. Changing it will only accelerate the life you have left in the trans.

 

Change the fluid. If nothing else drop the pan and refill. Seems silly that if someone is going to keep the car for any amount of time, they would NOT change the fluids. Lifetime trans fluid is ridic to me.

I have many vehicles that are 200k+ miles and I've completely changed the fluid by disconnecting the return line, pumping some fluid out. Refilling, pump out, refill...etc.. Doing so until what is coming out is cherry red. ZERO issues.

My CT200h has around 80k miles on it and it was never changed. Lexus says there's not need to. I changed the fluid last month and I pulled out dark fluid that looked like oil. I refilled it and now it's new and cherry red.

If you are having trans problems, then the thing is on the way out anyways. But if not, drop the pan and change the fluid. I plan on changing mine on the RCF when the time comes.

If it's anything like most modern cars and I'm sure it is. The procedure is something like you fill the system up, then get the car up to a specific temp via Tech stream and then open the drain bolt and let it drain off the excess until it's just slightly dripping, then close it up. I know my wife's NX is like that. My Mercedes is like that..etc. Obviously, I'm cutting out tons of details, but most modern transmissions have a similar fill procedure to get it to the correct level/temp..etc.

-Nigel

 

Great feedback from AlexA. I have done my GSF myself at 70k miles with Amsoil where I drained and fill 3x. I used the pinning of obd method to verify correct temp on the last filled. Pinning the obd is much more accurate than temp gun. The gear shifts appears to be faster. Also be sure the engine is running when doing the measurements otherwise will underfill the tranny.