ATF fluid a340 dex merc 3

[ripcord]

Any fluid marked as "Dex/Merc" that you find on the shelf today is intended by the manufacturer to meet the old Dexron IIIh spec. Due to licensing restrictions, it just can't be labeled as such.

There is so much confusion around this that it's almost comical. GM says that you may use Dexron VI interchangeably with the previous IIIh fluid in all GM vehicles, but I am unaware of Toyota or any other auto manufacturer saying the same thing regarding their cars.

 

[kschachn]

There is so much confusion around this that it's almost comical. GM says that you may use Dexron VI interchangeably with the previous IIIh fluid in all GM vehicles, but I am unaware of Toyota or any other auto manufacturer saying the same thing regarding their cars.

They don’t have to. It’s the licensing authority that determines the supersession. Same as motor oil API licenses.

 

[ripcord]

They don’t have to. It’s the licensing authority that determines the supersession. Same as motor oil API licenses.

I'm pretty sure there are no licensing authorities for transmission fluid. It's certainly not the API. The specs are manufacturer specific. That's why there were two interchangeable specs and two trademark names (Dexron III and Mercon) for the same fluid.

Asian manufacturers who used Dexron type fluids in their transmissions issued their own specifications and trademarks which were essentially identical to Dexron. Isuzu called theirs ATF-II and ATF-III, Mazda had M-II and M-III, Toyota had T-II and T-III, etc. Hyundai was SP-III.

 

[SwampSurvivor]

My a340 works great with Dex VI!

And mercon V. And regular III. But shifts the best with Vi

I've put 120,000 on it over the past 14 years. It's really not a picky transmission.

 

[kschachn]

I'm pretty sure there are no licensing authorities for transmission fluid. It's certainly not the API. The specs are manufacturer specific. That's why there were two interchangeable specs and two trademark names (Dexron III and Mercon) for the same fluid.

Asian manufacturers who used Dexron type fluids in their transmissions issued their own specifications and trademarks which were essentially identical to Dexron. Isuzu called theirs ATF-II and ATF-III, Mazda had M-II and M-III, Toyota had T-II and T-III, etc. Hyundai was SP-III.

Dexron is still a license, here is where you submit your sample and information if you wish to obtain that license:

Dexron Licensing site

 

[ripcord]

Dexron is still a license, here is where you submit your sample and information if you wish to obtain that license:

Dexron Licensing site

Yes, that is General Motors' licensing contact page, but they have withdrawn the Dexron IIIh and prior licenses and will only license Dexron VI and later specs. Other manufacturers specifications and trademarks are separate.

 

[kschachn]

Yes GM is the licensing authority for Dexron.

 

[ripcord]

Yes GM is the licensing authority for Dexron.

Sorry if we are talking past each other. I took your earlier comment to mean you were saying there are independent, industry organizations like the API that provide certification and specifications for transmission fluids

 

[kschachn]

Sorry if we are talking past each other. I took your earlier comment to mean you were saying there are independent, industry organizations like the API that provide certification and specifications for transmission fluids

Yeah sorry I was wrong too. I was only thinking of Dexron. You are correct on the other ones.