ATF Fluid Question, LEGIT

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I was thinking. I know, I know, that shocks some of you.
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I don't know if this has been discussed in this forum before and I don't feel like doing a search. Too complicated for me with the date thing.

Anyways, why are some ATF fluids that come in our vehicles synthetic and some are not? Some of the new Fords are using non-synthetic
ATF's. Is is simply a situation where the manufacturers are trying to hold costs down? (I have read where some mechanics recommend
conventional gear oil for diffs)

Most people hold Toyotas in high regard for their quality but neither of their ATF's (T-IV or WS) are synthetic. I guess I don't understand and maybe
never will.
 
It's really a time/temperature relationship to determine the "life" of the trans fluid.
You could run the old Dex III forever at 200F but it died pretty quick at 275.
So as a transmission guy you are always wrestling with the cooling system folks.
We went with a premium synthetic product at Allison so we could feel confident about the fluid life even if the operating conditions were consistently rigorous and be confident giving the customer a lengthy warranty.
It's overkill for grandpa tooling down the interstate in his diesel pusher, but just right for NYC refuse or Houston transit in the summer.
 
Great explanation! Thanks!

Why do you think Toyota only sells conventional ATF's? Just a money issue?
 
What is wrong with conventional fluid?

Serious question.

If 99% (or more) vehicles serve out their lives with conventional fluid, then conventional is fine. It works. Synthetic fluid has zero advantage in those applications.

Why should a manufacturer use a more expensive formulation when it's not needed and the average consumer (not BITOG member) doesn't care?

IF a manufacturer uses a synthetic, perhaps they have a reason to. Perhaps, in that application (performance, heat, towing, whatever) they have determined that it is worth the extra cost.

But not every car, not every vehicle, needs a synthetic fluid. Legit. Serious. Regular fluid works great.

Personal examples from cars I've owned*.

1. 1977 Oldsmobile, 200,000 miles on the original transmission, using DEXRON conventional, fluid. Nothing else was made back then. It was my first car and saw a lot of very hard driving. I was a kid.
2. 1990 Toyota 4 Runner. Lots of 4 Wheeling and rough use. Still on the road, 300,000 miles on conventional (DEX I, then II, then III, then Toyota Type-IV).
3. 2002 Volvo T5 Wagon, still being driven by my daughter, 200,000 miles on JWS-3309 fluid.
4. 2002 Volvo XC, still on the road, 265,000 miles using, wait for it, wait for it, conventional JWS-3309 fluid.

If I can get over 200,000 miles from a transmission that used nothing but conventional fluid, why do you want to spend more on synthetic?

Here is your logic applied to a different aspect of automotive manufacture: Why doesn't every car come with Z rated tires? Why are some companies using only H rated tires? Is it just for cost savings?

Same legit answer; not every consumer, not every vehicle, needs the performance that Z rated tires offer. Most are just fine with H rated tires. They'll never see the speed/heat that demands a Z rating.

If the base stock of a fluid matters to you, then feel free to change it out yourself. That's what I did on my Tundra at 25,000 miles. The Toyota WS fluid was bright red and looked great by the way, despite using the truck to tow.

So, even though I am a little OCD about fluids, the conventional fluid was holding up just fine in that application.

Just because something sounds better, or costs more, doesn't mean that it makes sense to use it.


*I've owned over 25 cars, and I have yet to blow up or replace a transmission. Done a few clutches along the way. I listed the cars that made it to 200,000 or more. I still own two of those listed. They're still in daily use. Most of the others were sold, or totaled, before reaching that number but the point remains: every single one of them ran fine on conventional transmission fluid.
 
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Excellent points, Astro14. Note, I'm merely asking a question and your answer makes a lot of sense.

Simply put, the way I understand you, is that generally speaking, synthetic ATF's are not deemed necessary by certain manufacturers.

I still use Toyota branded Dexron lll in my 2002 4Runner
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Originally Posted by Chris142
Originally Posted by dogememe
Very very few Toyota vehicles are used for severe service.

What about the ones in south america,Africa etc?

Most of them are manual shift
 
There are synthetic labeled fluids made with low cost (minimum spec) additive packages made and sold out there. Then you have high quality mostly non synthetic fluids but with a very superior grade additive package that are better in nearly every category than a low grade "synthetic" fluid. And the non syn might outperform the low grade full syn in most categories. Best to change whatever fluid you decide to use at a reasonable interval before the fluid is in bad shape. If you want to go longer, then use higher grade full synthetic fluid along with increased filtration efficiency and cooling which will allow you to increase change intervals safely. I also recommend this for towing use. Just my 2 cents backed up with 40 years experience.
 
I think that if there is concern over temperatures in a transmission it would be advisable to add a bottle of the appropriate Lube-Gard. Remember when there were no synthetic fluids for transmissions? How long did they last? It seems that back in the 1970 a GM Turbo 350/400, Torqueflite, C6 lasted about 100k miles. The Japanese transmissions were pretty rare in automatic form back then so I don't recall how long they were lasting. So it shows that the transmissions and fluids are both probably better nowadays.
 
I am no industry expert, so I can only speculated based on educated guess. It cost money to retool to use a different type of fluid, so different type of fluid is based on what each manufacturer is used to. I imagine they won't change unless there is a reason to. For example, new technology require formulation of fluid or if there is a cheaper way to make fluid.

Companies may also merge or share technology, resulting in perhaps changes. Different fluid occur because companies have different branches of development, which result in different types of fluid that does the same thing. There are more than 1 way to skin a cat after all.

Paul
 
To Astro14s point above. My extended family - Mom, Dad, sister - have owned over 15 Volvos since 1973.
The highest mileage was 336,000 on my 89 740.

I’ve always used the Volvo recommended transmission fluid and change interval. All the fluids have been conventional until recently. I now use full syn DEX IV in the 240s.

There has never been a transmission failure or need for service other than a pan gasket in any of the cars.
 
Even Dexron VI specs have been met with a blend for years …
P66 is now a big OEM provider and makes Grp3 through HP rather than HC process …

I just bought 16 quarts of Valvoline Dex VI “synthetic” … what does that label mean ?
Nothing less, nothing more than Dexron approved and Mercon LV “recommended “ …
(and was even cheaper than SuperTech) …
 
Even Dexron VI specs have been met with a blend for years …
P66 is now a big OEM provider and makes Grp3 through HP rather than HC process …

I just bought 16 quarts of Valvoline Dex VI “synthetic” … what does that label mean ?
Nothing less, nothing more than Dexron approved and Mercon LV “recommended “ …
(and was even cheaper than SuperTech) …
VW used in first DSG gearboxes synthetic fluid. They had issues in the beginning, that have been partly resolved with semi-synthetic fluid.
 
Even the non-synthetic ATFs are very highly purified and processed. Transmission fluid is designed to get beaten to death.
 
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