Devh

I'm not doubting the wear aspect and the acceleration of wear as the fluid gets older however I do not see that becoming an issue for the normal expected service life of the car. The way I see it there are a lot more weaker links to the puzzle then the fluid one of them happens to be the anecdotal incidences of the risk of fluid replacement or flush. When I mention fluid flush I'm not referencing the machine flush service, I'm mostly writing about actual replacement of all or part of the fluid. New fluid will begin cleaning the transmission crud that has been layering on all the metal surfaces and this might end up getting dislodged and resulting in clogging the passages which can result in transmission issues. Also if the actual procedure of a transmission re-fresh is not performed properly or at the correct level you can introduce another variable to the mix.
This is a double edged sword that I have wrestled with but in the end nothing last forever and for all you know an accident that may total the car completely will take whatever expectations of longevity out the window in an instant.

Fhobbs

Another thing to maybe consider is (maybe old school) that transmission shops recommend changing the fluid to unsuspecting customers. They know that putting new vital fluid in a used transmission works actively and the stronger fluid promotes further decay and failure of already used and weak clutch pads. A new or rebuilt transmission needed!

Lavrishevo

iTrader: (1)

I won't beat a dead horse but the general rule of thumb is that you avoid flushing all together. If you have your transmission flushed early, like every 30k, it should not be a problem but overall it's a more risky procedure. You mention gunk or sludge possibly dislodged that would clog something. Gunk is built up in the transmission how? By not changing the fluid. This is why a drain and refill is the safest and preferred method. Anyway, I only let Lexus service my transmission. Anyone care to comment on why Lexus says to not change the transmission fluid in the United States alone? It's the same transmission in every other 460 around the world....

robert1408

The short answer is the Magnuson-Moss Warranty Act in the USA. Under that law, auto manufacturers cannot require customers to use dealer service to maintain warranty coverage unless that service is free. In many other countries manufacturers can require dealer servicing to maintain your warranty. I think Lexus would rather pay an occasional warranty claim caused by used up fluid than warranty these expensive transmissions damaged by improper fluid service at Goobers' Garage.

Like many modern automatics, our trannys are very sensitive to fluid level, fluid type and technique used to service them.

Devh

Gunk is built up in layers on every metal surface due to oxidation of the fluid and as a result of heat. When you add new fluid it acts as a detergent stripping off the varnish and suspending it to where it finds its way to occluding passages. This is why transmission fluid flushes as well as switching to synthetic from dyno oil for the engine late in the game can be a catastrophic disaster in the making.
Some transmissions like the BMW has a transmission filter that is replaced with the pan assembly when it has to be serviced which is a good idea but it may not be as effective given the age of the transmission.
I will agree that if you feel the need to change your transmission fluid regularly you need to do it every 40k miles otherwise it's risky. Even then as I said before if the job is not done right and you miss the mark of how much fluid to add as Robert has stated you can goof the transmission.
I don't even blindly trust the Lexus mechanic for this kind of work.
The bigger question is why do it at all if transmissions are not failing left in right because the fluid was not changed. You are more likely to have something else go majorly wrong with the car in the long run of plus 200K miles like worn out piston rings that it makes the car not worth the cost to fix anyway.

roadfrog

Still.........why only US market cars are exempt from this service? Canada and everywhere else requires this service at 60k AND diff fluid at 110k miles.

I knew a guy who NEVER (EVER EVER) changed his oil......not once. He just topped up when required. even the oil filter was in the car for years. He sold that car with 80k miles or so and never dropped a penny in the motor. No blue smoke....nothing. Still, I'm not prepared to take thjat chance with my car. So I change the oil....because it's a good thing. Same for the trans IMHO.

Devh

I also have heard of stories like this in regard to not changing the engine oil. That is not wise or even remotely the same thing as it goes way outside the bounds of what is normal and it's not recommended by the manufacture.
People including myself had a hard time at the turn of the century excepting longer then 3k mile oil changes, 0W oils and Toyota long life coolant but the engineers have been proven right.
There are still some people who insist on changing their timing chains at 60k like the timing belt.

roadfrog

Fair enough. However, unlike some companies EXTENDING oil change intervals, some are shying away from the "lifetime" label on transmissions. Some are calling "lifetime" 60k miles. My BMW e65 (with no dipstick to check levels), WAS lifetime, but BMW then stated that fluid chould be changed (I forget what intervals). MB did the same as did VW. In fact ZF, who manufacture the trans in BMW, Corvette, and others, deny that their trans are "lifetime" and reccommend 60k mile changes.

Still...I wonder how Lexus "USA" would explain why their requirements are lifetime and Lexus "everywhere else" is not. If they were honest, they would respond, "marketing", to compete with the claims made by the other manufacturers. When the warranty runs out, they don't care that you never changed the fluid.

Devh

I think your logic is sound and I'm more inclined to believe that we cannot trust the manufactures claims if it was VW or BMW as they seem to miss the boat on a lot of things. Also I remember GM promoted a car that did had a lifetime engine oil and it was a monumental disaster along with their Dexcool radiator fluid. I think we do need to contact Lexus corporate in a very deceptive way to find out why the Canadian recommendation is different. I think one of us should contact them stating that they plan to immigrate to Canada or the US and if they still had to follow the recommended service interval for the transmission. Then we can get a clue as to why they made the recommendation.

Toyotas philosophy and strategy is keeping their customer base and except for the sludge monsters engines they made in the past they are heavily invested in keeping their reputation.
Toyota transmission on the whole has always had a great reputation for durability even in the absence of recommended service intervals which many people have abused.

jlawr

Devh,

I vote for YOU to call Lexus Corporate and report back to us.

roadfrog

LOL. I WOULD be curious as to how they explain it.

1BlinkGone

I cannot speak to Lexus vehicles, but the scare tactics about flushing a transmission seems ridiculous. I was in fleet maintenance for a number of years, and I never EVER saw any transmission problems exhibited by a properly done (and refilled) flush. That doesn't mean just dropping the pan & R&R'ing the filter, but to flush the system entirely.

One thing to remember that in general, automatic transmission fluid is a VERY high-detergent fluid; so much so that one of the tricks to freeing a stuck (by varnish or other crud) hydraulic lifter in an engine is to put a bit of ATF in the crankcase, drive it for about 30-50 miles (or less) so the lifter unsticks and then do an oil change. I've never, ever, no matter how cruddy the transmission fluid, ever saw varnish in a valve body.

IMHO, the ones telling you NOT to flush the trans, want to sell you a replacement transmission.

Today, there are additives that you can add to your AT before a flush that will pretty much eliminate any potential crud gumming up a valve body. No fear here. I can attest to the longevity of transmissions that have the fluid changed. YMMV.

roadfrog

FWIW....I just booked an appointment with Toyota for a trans fluid change on Wednesday. They quoted 148 dollars. They also explained that the car will be hooked up to Techstream for proper operating temperature drainage/refill just like it's supposed to be done. When I explained to them that my U.S. brothers here at CL have "lifetime" fluids according to Lexus Corp, he was aghast. He was sure I was making stuff up to avoid getting the service done. He could not explain why only Lexus' in America have lifetime fluid.

gemigniani

Absolutely not true. New fluid extends the life of all internal parts and seals of an Aisin. I have two 41 year old Toyota automatics that are still running fine because I put fresh fluid in them when they were about 25 years old and have kept fresh fluid in them ever since.

Clean fluid is especially important on the newer Toyotas because it helps prevent the electronic shift control solenoids from getting sticky and/or failing.

Gotcha350

BINGO!!!!!!! These solenoids are failing left and right on the 6spd transmission with no fluid change around 130k because they are becoming stuck....and of course Lexus wants to replace the entire transmission because they won't do 'internal repairs'.

I had mine changed at 60k on my 08 GS and will have it done every 30 there after. And I have done the same on my 11' Infiniti QX56 and that was dealer recommended even though it also has lifetime fluids. Both transmissions were shifting smoother after the changes....

And I'm not going to mention the amount of water pumps that are failing with the LLC around 60k...all the manufactures want is to get you out the warranty period...I don't mind paying for services if I'm going to shell out 60k+ for a vehicle...its called peace of mind....