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Automatic transmission fluid... Permanent?

A number of new models have sealed automatic transmissions. Not even a dipstick. The owner’s manuals say nothing about checking the level and do not mention fluid replacement. Apparently this fluid is supposed to last for the life of the car. Should we accept this premise?

…only if you relish the thought of overhauling that trans at…somewhere around 120k-150k miles.

Don’t forget that car makers are in more or less of a competition to be able to claim the lowest maintenance costs over the life of the vehicle. In fact, some magazines (Kiplinger’s and Money come to mind) actually rate cars based on which ones require the least maintenance (according to the mfr.) As a result, car manufacturers know that they can boost sales by claiming that their cars need less maintenance than other makes. However, neither the magazines nor the vehicle manufacturers ever talk about repair costs over the long term on these same vehicles!

And, let us not forget that lack of trans maintenance is not likely to lead to trans failure during the term of the vehicle’s Powertain Warranty. The mfr has no concern about trans failures that take place after the warranty has ended, when the vehicle owner is stuck with the cost of major repairs.

If you want to have as much assurance as possible that your trans will function properly for the long-term, you will adhere to the conventional wisdom about changing the fluid every 3 years/30k miles.

That IS the life of the car…drive it till it breaks !
I hate that premise.
It seems the designers are are wimping out to the public’s practice of not maintaining.
They guess that since the public wants to just drive it till it breaks…then that’s what they’ll give us.

I can’t even stomach the idea of no changable fuel filters !

Motor oil will also last the life of a car. So perhaps we should all stop changing that too…

(Or, in other words, what VDC & ken green said).

There is no “life of the car” - as a concept it simply doesn’t make sense. Unless they get completely wrecked by rust or accident, the life of a car is exactly as long as you keep fixing it.

Volkwagen came out with this idea in the late 1990’s. They were actually selling cars using the ‘lifetime fluid in the transmission’ line. But, the transmission company ZF, that builds all of VWs transmissions, debunked this with a very public press release. They said the ZF company line is the fluid should be changed every 60,000 miles to insure reliability of the transmissions.

In 2002, Ford Explorers also came with a sealed transmission. BUT, they also recommended the transmission still be serviced regularly. It took a special scan tool to check the fluid level. The trick was that the dealer was the only one equipped to do the service… until the independent shops were able to get the equipment to do the job.

Lifetime warranty, oops lifetime over. Now you pay.

The problem arises in how the term “life of the vehicle” is defined…The OWNER of the vehicle thinks that term really means “forever” while the manufacturer of the vehicle feels 10 years is plenty long enough…

Today, in many cases, it’s the failure of this component, the transmission, that determines “the life of the car”…They have become so expensive to repair, and the repair outcome so uncertain, that transmission failure frequently terminates many cars that are otherwise still serviceable…

That premise is just one of a number of factory recommended premises that I will never agree with.

Let the Feds mandate that all automatic transmissions be warrantied for 150-200k miles minimum and the car makers will be falling over themselves recommending 20k miles fluid changes.

It is lifetime of vast majorty of new car owners. keep cars.

One of the reasons I passed up the Jeep Cherokee 05-11 models as my new car. The transmission has a dipstick hole that is capped and says dealer only. You can but the dipstick, but need a scan tool to get the transmission fluid temperature and then graph the level for the fluid.

But I think, like the rest of you, I am in the minority. Most people never bothered with the transmission or much of other fluids until the car came to a standstill.

Any fluid has a life more dependent upon use then time. Excessive heat to contamination are more important then time. Theoretically, any fluid, motor oil included, can be lifetime. Like wise, under certain conditions, it could be changed immediately after use. I have no problem with running transmission fluid in a light car under ideal conditions for 100k. I have a problem asking the fluid in an SUV used for towing and off road go much over 30K and have under real hard conditions, towing heavy equipment a long distance, changed immediately after use.
I know some who change trans fluid following each plow season in their trucks. Seems like good insurance to me but a waste of money in a Camry.

Where’s Transman? I am really in a quandry myself. I have no dipstick and can’t even find the access hole for adding fluid that’s supposed to be down by the axle. Two dealers have told me they just flush them, but it has the normal pan and filter. See other post where flushing caused problems. So I really don’t want to flush it without dropping the pan, but if you drop the pan, you’ve got to add through the access hole somewhere. I’m not sure I’m trusting the dealers.

@Bing; what car is it? The dealer would have to add fluid and measure the level, could it be a nut like the manual transmissions? I know the newer Camry’s have something like that.

I own two vehicles that have that type of transmission (Toyota and Lexus).

I replace the fluid every 40-50k miles. It’s one of those jobs easier on a lift (which I don’t have). So I take it a transmission specialist near me. And the fluid looks like it needs to be changed.

I’m not a fan of this philosophy. Especially with my 4runner because I do a lot of towing during the summer. It’s not an expensive job (about $90 each vehicle). Far cheaper replacing the tranny fluid every 40k miles then replacing a transmission at 200k miles.

I could live with lifetime fluid if the trans also came with a lifetime transferable warranty.

@circuitsmith - Good point…Toyota (and others) are saying the fluid will last for ever…never said the transmission would last that long.

I still dont get how some cars dont have an Oil Dipstick… Just seems like a bad way to cheap out, but its always on high end cars like MB and BMW’s…

It’s becoming standard now.

All Toyota’s since 2006 are that way. Toyota is NOT considered a high-end car.

And I agree…I don’t like it either.

Is the jury still out on whether these “sealed” transmissions that use the WS (World Standard) fluid can do fine extending the change interval? I asked that question of a Toyota dealer and the reply was “don’t even bother touching it till 100K miles”.

Today’s engine oils enable the oil change intervals to extend way beyond the traditional 3K mark. In practice, how are longer trans fluid change intervals with WS fluid working out? Are failures occurring at a similar rate to non-WS fluid transmissions?

Is the jury still out on whether these “sealed” transmissions that use the WS (World Standard) fluid can do fine extending the change interval? I asked that question of a Toyota dealer and the reply was “don’t even bother touching it till 100K miles”.

Who knows…and why take the chance? I’m not going to take a chance with a $7,000 transmission.