Dex III vs DexVI
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Racer
Joined: Oct 2002
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From: Fayetteville, PA
Dex III vs DexVI
Has anyone had any problems after using DexIII and then switching to DexVI? I have noticed slipping problems in 4th gear in my 97 4l60E and i fell it may be the tranny fluid.
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From: Howell Michigan
St. Jude Donor '09-'10-'11
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From: Dyer, IN
What is the history here? When was the fluid changed? Why was it changed? Was the fill procedure followed? Did you have problems before the fluid change? Was it power flushed?
Le Mans Master
Joined: Sep 2003
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From: Longview Texas
I thought you were only supposed to use Dexron VI in transmissions specifically designed for it. The fluids are not interchangeable.
I have also heard of people putting Dexron VI in manual transmissions designed for III, and it burned them up in short time.
I found that they are suppposed to be backward compatible, but I always hesitate to use an upgraded product on an older car that was not designed for it.
I have also heard of people putting Dexron VI in manual transmissions designed for III, and it burned them up in short time.
I found that they are suppposed to be backward compatible, but I always hesitate to use an upgraded product on an older car that was not designed for it.
Last edited by TEXHAWK0; Jan 12, 2012 at 10:26 AM.
Tech Contributor
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From: Howell Michigan
St. Jude Donor '09-'10-'11
I thought you were only supposed to use Dexron VI in transmissions specifically designed for it. The fluids are not interchangeable.
I have also heard of people putting Dexron VI in manual transmissions designed for III, and it burned them up in short time.
I found that they are suppposed to be backward compatible, but I always hesitate to use an upgraded product on an older car that was not designed for it.
I have also heard of people putting Dexron VI in manual transmissions designed for III, and it burned them up in short time.
I found that they are suppposed to be backward compatible, but I always hesitate to use an upgraded product on an older car that was not designed for it.
DEX III is no longer being made
DEX VI works well in my 2000 C5 6 speed manual with paper backers. 20K+ miles, 2.5 years of use. I’m changing it again next spring with Dextron VI. The transmission works better with Dextron VI than it ever did with Dextron III.
Le Mans Master
Joined: Sep 2003
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From: Longview Texas
Last time I changed my manual transmission fluid, GM still made, and recommended, using what they call "manual transmission and transfer case fluid", which I suspect is still Dexron III.
Part number 88861800
Last edited by TEXHAWK0; Jan 12, 2012 at 08:45 PM.
Racer
Joined: Aug 2008
Posts: 494
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From: Fairbanks, Alaska
Internet Myth – Not True - it is 100% backward compatable.
DEX III is no longer being made
DEX VI works well in my 2000 C5 6 speed manual with paper backers. 20K+ miles, 2.5 years of use. I’m changing it again next spring with Dextron VI. The transmission works better with Dextron VI than it ever did with Dextron III.
DEX III is no longer being made
DEX VI works well in my 2000 C5 6 speed manual with paper backers. 20K+ miles, 2.5 years of use. I’m changing it again next spring with Dextron VI. The transmission works better with Dextron VI than it ever did with Dextron III.
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Le Mans Master
Joined: Aug 2000
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From: Austin TX
Internet Myth – Not True - it is 100% backward compatable.
DEX III is no longer being made
DEX VI works well in my 2000 C5 6 speed manual with paper backers. 20K+ miles, 2.5 years of use. I’m changing it again next spring with Dextron VI. The transmission works better with Dextron VI than it ever did with Dextron III.
DEX III is no longer being made
DEX VI works well in my 2000 C5 6 speed manual with paper backers. 20K+ miles, 2.5 years of use. I’m changing it again next spring with Dextron VI. The transmission works better with Dextron VI than it ever did with Dextron III.
Tech Contributor
Joined: May 2008
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From: Howell Michigan
St. Jude Donor '09-'10-'11
It’s your car; use what you want where you want. For me, I’ll stick with what was recommended to me by the real experts in the industry on Corvettes. They haven’t let me down on any of their suggestions.
Keep in mind that products documented in the manufactures manuals and services bulletins is your safe bet. GM recommends 88861800, and no, it is NOT Dexron III.
Dexron-III licensing system no longer exists, so, you can buy products that claim to be Dex-III, Dexron-III or any other derivative name, but you have no guarantee it is anything close to the original fluid. If you have doubts, stick with 88861800. For me, I’ll stick with Dexron VI. My car my choice.
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From: Dyer, IN
Yep, I’m sure you are right. Only working 35 years for the company that manufactures the Corvette, with the last 9 year as part of the Corvette engineering team, having talked with the engineer responsible for spec’ing the fluid properties for transmission in Corvettes, yep, have no idea.
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From: King George VA
This issue is somewhat confused as Dexron III and VI are (or were) both specifications and product names. The main differences between the two specifications is that Dexron III could be met by a conventional basestock, whereas Dexron VI requires a better basestock, probably either a semi-synthetic or a Group III synthetic basestock. But, while the GM branded Dexron III was conventional, there are many synthetics on the market that meet the original requirements for this spec. The other main difference is that the viscosity of the Dexron VI is about 40% lower than that of the Dexron III to help GM's CAFE rating. I personally do not feel comfortable with that drop despite GM saying Dexron VI is backwards compatible. In my GM vehicles that originally required Dexron III, I use AMSOIL's Dexron III product vice the lower viscosity Dexron VI (or aftermarket alternative).
AMSOIL's offerings:
Dexron III: AMSOIL Multi-Vehicle ATF (Product Code ATFQT)
Dexron VI: AMSOIL Low Viscosity Universal Automatic Transmission Fluid (ATL) (Product Code ATLQT)
AMSOIL's offerings:
Dexron III: AMSOIL Multi-Vehicle ATF (Product Code ATFQT)
Dexron VI: AMSOIL Low Viscosity Universal Automatic Transmission Fluid (ATL) (Product Code ATLQT)
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Tech Contributor
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From: Howell Michigan
St. Jude Donor '09-'10-'11
This issue is somewhat confused as Dexron III and VI are (or were) both specifications and product names. The main differences between the two specifications is that Dexron III could be met by a conventional basestock, whereas Dexron VI requires a better basestock, probably either a semi-synthetic or a Group III synthetic basestock. But, while the GM branded Dexron III was conventional, there are many synthetics on the market that meet the original requirements for this spec. The other main difference is that the viscosity of the Dexron VI is about 40% lower than that of the Dexron III to help GM's CAFE rating. I personally do not feel comfortable with that drop despite GM saying Dexron VI is backwards compatible.
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From: King George VA
Where are you finding that Dexron VI is 40% lower than Dexron III? Looking at the data below, The Dexron III starts off at 20% higher, not 40% and Dexron VI holds a more consistent viscosity. In fact Dexron VI shows higher viscosity, almost 17% better than Dexron III after a short amount of time.
Your link doesn't work, but I think you meant this one:
GM Dexron VI
I based my 40% difference on the viscosity difference of the Dexron III vs Dexron VI as new out of the bottle for some aftermarket companies as I can't get the actual specs for Dex III and VI. Using the data presented by Sandy Blogs the difference would be 7.5/6.0 = 1.25 or 25% higher.
But, where I disagree with you is that while this graph shows GM Dexron III shearing rapidly down to ~5.0 cSt, which is exactly what the factory fill GM Dexron III did in my 06 CTS-V, after market fluids such as the AMSOIL ATF which use synthetic basestocks do not shear down and stay at the original viscosity of ~ 7.4 cSt. This is why I think many get confused by Dexron III/VI both being products and specs. GM's Dexron III sheared down very rapidly as GM's own data shows. But that does not mean all Dexron III products shear down that fast.
Racer
Joined: Aug 2008
Posts: 494
Likes: 1
From: Fairbanks, Alaska
Yep, I’m sure you are right. Only working 35 years for the company that manufactures the Corvette, with the last 9 year as part of the Corvette engineering team, having talked with the engineer responsible for spec’ing the fluid properties for transmission in Corvettes, yep, have no idea.
It’s your car; use what you want where you want. For me, I’ll stick with what was recommended to me by the real experts in the industry on Corvettes. They haven’t let me down on any of their suggestions.
Keep in mind that products documented in the manufactures manuals and services bulletins is your safe bet. GM recommends 88861800, and no, it is NOT Dexron III.
Dexron-III licensing system no longer exists, so, you can buy products that claim to be Dex-III, Dexron-III or any other derivative name, but you have no guarantee it is anything close to the original fluid. If you have doubts, stick with 88861800. For me, I’ll stick with Dexron VI. My car my choice.
It’s your car; use what you want where you want. For me, I’ll stick with what was recommended to me by the real experts in the industry on Corvettes. They haven’t let me down on any of their suggestions.
Keep in mind that products documented in the manufactures manuals and services bulletins is your safe bet. GM recommends 88861800, and no, it is NOT Dexron III.
Dexron-III licensing system no longer exists, so, you can buy products that claim to be Dex-III, Dexron-III or any other derivative name, but you have no guarantee it is anything close to the original fluid. If you have doubts, stick with 88861800. For me, I’ll stick with Dexron VI. My car my choice.
Dex III works just fine and i dont have any issues so you can act like a bag of chips and brag on here but when it works just fine it makes you look like a dumbass.
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From: Dyer, IN
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From: Howell Michigan
St. Jude Donor '09-'10-'11
You really hurt my feelings...
Tech Contributor
Joined: May 2008
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From: Howell Michigan
St. Jude Donor '09-'10-'11