Gil Smash

I was just looking over in the high mile thread and noticed there was a decent amount of people who have had transmission flushes done and I was wondering what mileage that would be a good idea, my car (01 LS430) has some hesitation and shifting roughness occasionally and I was thinking it may benefit from a flush but I've heard conflicting reports from people as to whether or not its a good idea.

Pamperme

Out of curiosity, how many miles do you have, and how regular have you had the transmission fluid changed in the past?

sajack

Does Lexus recommend this?

Jabberwock

01-03 LS has AT fluid meant to be periodically replaced based on service severity and miles. I think most dealers recommend yearly AT drain and fill of AT for most types of driving. Be aware that typical AT drain and replacement of apprx 3 of 12 total quarts in the AT obviously only partially replenishes fluid..but if this process is done yearly some people think the process keeps the overall condition of the AT fluid in decent shape of car's lifetime. Not everyone agrees hence the flush and fill machines - which on the surface sounds like a much better plan.

After a few years of use however there started to be anecdotal evidence that some "power" AT flush machines might be causing worn bits/debris inside the AT to become more disbursed than normal and possibly be causing blocked passages in the AT and cause problems. But not all flush machines and process are the same.



Or you can have the Toyota or Lexus dealer do a drain and fill repeat process for you, or they also have a AT flush machine - i think the newer machines have been improved to avoid causing issues - but I would ask what they recommend.

Or you could also buy a case of Toyota AT fluid drain and drain and fill your own AT diy - its easy. Drain and fill, drive for a day or so and repeat 5-6 times...or until AT fluid being drained looks nice and clean.

sajack

My '02 owner's manual does not recommend changing the transmission fluid unless:
1. Drive on rough, muddy, or snow-melted roads.
2. Drive on salt-covered roads
3. Drive on dusty or unpaved roads.
4. Extensive idling or low-speed driving for long distances
5. Towing
My car hasn't been used for any of that, so I'm not paying anybody to screw with it. There is a pretty good chance that I would just be asking for trouble if I did.

Gil Smash

Im at 130k now and unless it was part of the regular service done by Lexus it has never been changed.

sajack

So, how many of you have experienced transmission failure in your LS430?

Gene01

I thought I might add what a trusted Lexus mechanic told me.
He recommended a "fluid exchange" on my '05 LS430 (with the "permanent" WS ATF).
I was rather shocked that he said that, but he quickly pointed out that a fluid exchange is NOT the same thing as a "power flush" (which he did NOT recommend). I just didn't understand the proper terminology.
He also stated that he had exchanged ATF on a number of WS cars, and found that the fluid looked bad after about 30 to 60 K miles.
I would guess that the fluid exchange has about the same effect as multiple drain/fill cycles as described above, except that drain/fill is more of a hassle on the WS cars since they were not designed for it.