[cary]

I am putting this in its own thread because how ATF fluids are labeled has been changed as a result of General Motors poor handling of the licensing of the name "Dexron".

Dexron is a specification put forth by General Motors for Transmission Fluid. Each new specification automatically includes the prior specification. So Dexron III fluid satisfies all requirements for Dexron II.

Periodically, we have had people ask the question "My manual says Dexron II, I can only find Dexron III, is this ok to use?" The answer is yes because of the later specification, includes the earlier.

Now we have a new issue. GM has put out Dexron VI. Where did Dexron IV and V go? GM was worried that people might get confused between the Ford Mercon V and their fluid, so they just skipped IV and V, go figure.

As part of putting out Dexron VI, GM has stopped licensing the use of the name Dexron III and doesn't want any bottles to reference it. So what has happened is that Dexron III fluids now say things like "for use in GM vehicles before 2005."

So what ATF do you use in your 80 series now?

1) Any fluid labled Dexron VI.
2) Multi vehicle ATF fluids that have some indication that they are "Dexron III" or "for use in GM vehicles 2005 or before."


Here is the actual GM press release, note what I have highlighted:

General Motors DEXRON®-VI Global Service-Fill Specification

During early 2005 General Motors released a newly developed automatic transmission fluid (ATF) for the factory fill of all GM Powertrain stepped gear automatic transmissions. The new fluid provides significantly improved performance in terms of friction durability, viscosity stability, aeration and foam control and oxidation resistance. In addition, the fluid has the potential to enable improved fuel economy and extended drain intervals. Since the performance of the new fluid far exceeded that of the DEXRON®-III service-fill fluids available at the time it became necessary to upgrade the DEXRON® service-fill specification in order to ensure that similar fluids were available in the market for service situations. This latest upgrade to the service- fill specification is designated DEXRON®-VI.

Since General Motors introduced the first ATF service-fill specification in 1949 it has been periodically necessary to upgrade the specification. This upgrading process ensures that available service fill fluids are of an appropriate quality for use in transmissions that have been designed around the factory fill fluid performance. It should be noted that, as with previous upgrades, DEXRON®-VI fluids are designed to be backward compatible with earlier transmission hardware. More importantly, earlier type fluids are not forward compatible with transmission hardware that was designed to use DEXRON®-VI fluid, i.e. DEXRON®-III is not compatible with the most recently designed transmissions, and the use of these earlier type fluids could result in transmission damage. All current calibrations and certification tests are now conducted with DEXRON®-VI ATF. DEXRON®-III fluids should not be used for these applications where the owners manual recommends the use of DEXRON®-VI. GM does not license or support obsolete ATF specifications or the use of fluids that are being marketed against cancelled specifications.

All DEXRON®-III licenses expire at the end of 2006 and will not be renewed. Beyond that date GM will only support the use of DEXRON®-VI fluids for use in Hydra-Matic transmissions. Fluids sold in the market after that date bearing claims such as “suitable for use in DEXRON®-III applications” or similar wording should be avoided. DEXRON®-VI licensed fluids are fully backward compatible and can be used in all applications covered by earlier GM ATF specifications.

The use of unlicensed fluids and/or non GM approved aftermarket additives may prove detrimental to transmission performance and void warranty coverage.

There is a published list of GM-approved brands of DEXRON®-VI (see page two of this release). This list represents the companies who have conducted the appropriate testing and received GM approval. Company name, license number, and brand name are shown. This list will be updated on a regular basis as more approved products are added.

[Ting]

Thanks Cary...

My question is ...Do you recommend this M1 ATF? What do you use in your truck?

[cary]

Personally, I use Redline D4 ATF. I do this for two reasons. 1) I tend to like Redline gear oils, having good luck with them for 15+ years. 2) They are local to me and relatively inexpensive compared to what others pay (I pay $25 per gallon). If I didn't use the Redline Gear oils and ATF, I would use Mobil 1.

[tomatopants]

That confused the hell out of me yesterday when I went to buy transmission fluid for my buddy's Nissan Stanza....

Thanks for clearing that up.

[lathamb]

So...I picked up a couple bottles of Mobil 1 Synth ATF Labeled "Mercon V" but also says "Multi use formula recommended by ExxonMobil for Use in 2005 and earlier GM vehicles. I'm assuming this is good to go in the 80.
Ben

Edit: never mind, search found it for me.

[gray]

Originally Posted by Ting

Thanks Cary...

My question is ...Do you recommend this M1 ATF? What do you use in your truck?

I have used Mobil 1 synthetic ATF for 20 years in my LC's. I believe it
is better now that it was 20 years ago.. I recently flushed my system
in early 2007 and put in Mobil synthetic ATF (Dexron); it shifts perfectly, better than it has since I bought it. I would not use any ATF that says anything other than Dexron or GM, etc
as in the main thread. Not Mercon, Multivehicle, Chrysler, or Ford, etc. Only GM/Dexron, IMHO based on my experience.

g

[gray]

Originally Posted by lathamb

So...I picked up a couple bottles of Mobil 1 Synth ATF Labeled "Mercon V" but also says "Multi use formula recommended by ExxonMobil for Use in 2005 and earlier GM vehicles. I'm assuming this is good to go in the 80.
Ben

Edit: never mind, search found it for me.

If in doubt, call the Mobil Tech line and ask them which of their
products they recommend for your specific vehicle;

Mobil Tech Line: 800-662-4525

[RavenTai]

RE: M1 ATF


been running it for over 70K in the 80, and also in a previous vehicle, I like it,

[lathamb]

The Mercon V thing threw me, this thread clears it up:

Mobil 1 synthetic ATF?

They changed the label.