Dexron III vs. Dexron VI

[BodybyFisher]

Now that I have my tranny substantially disassembled, I was thinking of using Dexron VI. In searching the net, I did find a negative experience with it > http://www.ls1tech.com/forums/showthread.php?t=408752

On the other hand this is impressive:

http://www.havoline.com/products/na/trans_md3.html

I vaguely recall a member reporting sharper shift with VI. Has anyone tried it?

Here are the specs, they look impressive:

DEXRON®-VI ATF

General Motors Powertrain has recently upgraded to DEXRON®-VI ATF with the start of 2006 vehicle production.

Only 2005 and prior models that currently use DEXRON®-III may use DEXRON®-VI as a replacement.

All 2006 and future models that use DEXRON®-VI are to be serviced with DEXRON®-VI fluid only.

DEXRON®-VI is an improvement over DEXRON®-III in the following area:

DEXRON®-VI

Extended Factory Fill For Life 160,000 km (100,000 mi) For Cars and Light Duty Trucks*

80,000 km (50,000 mi) (Severe Use) For Cars and Light Duty Trucks*

Clutch Friction Stability Improved 100%

Clutch Durability Due To Fluid Improved 120%

Oil Film Thickness Increased 20%

Fluid Oxidation Improved 100%

Foam / Aeration Improved 150%

Shear Stability Improved 200%

* These ATF change intervals remain the same as DEXRON®-III for the time being.

2006 Transmission Fill and Cooler Flushing

Some new applications of the 6L80 six speed transmission will require the use of the J 45096 -- Flushing and Flow Tester to accomplish transmission fluid fill. It is highly recommended that the clean oil reservoir of the machine be purged of DEXRON®-III and filled with DEXRON®-VI

[adallak]

Improved 100%, improved 200%, improved 150%.... sounds like "the soap kills 99% of bacteria"... Who writes all this BS?

[BodybyFisher]

I wanted to add that my fluid (Dexron III) was incredibly clean. It was changed at 50,000 miles by the prior owner and I have 96K now. I am shocked to see the fluid still pink.

[KHE]

I'd use the Dexron III if it were my car. The synthetic is not worth the expense.

[Spurlee]

This weekend I'm changing the fluid in my manual transmission - it calls for Dexron III. The new stuff from Mobil 1 is Mercon V - is says it's good for 2005 and earlier GM vehicles where Dexron is specified.

[BodybyFisher]

I bought Pennzoil Dexron III, $8.79 a gallon, vs. $4.99 a quart for Dexron VI and I need 13 qts.

[adallak]

I bought Pennzoil Dexron III, $8.79 a gallon, vs. $4.99 a quart for Dexron VI and I need 13 qts.

Now, your project is getting really expensive!

[Logan]

Here is the GM bulletin about it..I highlighted one part of it...interesting..

The content of this bulletin does not apply to manual transmissions or transfer cases. Any vehicle that previously required DEXRON®-III for a manual transmission or transfer case should now use P/N 88861800. This fluid is labeled Manual Transmission and Transfer Case Fluid.

Consult the Owner's Manual or Service Information (SI) for fluid recommendations.

Some of our customers and/or General Motors dealerships/Saturn Retailers may have some concerns with DEXRON®-VI and DEXRON®-III Automatic Transmission Fluid (ATF) and transmission warranty claims. DEXRON®-VI is the only approved fluid for warranty repairs for General Motors transmissions/transaxles requiring DEXRON®-III and/or prior DEXRON® transmission fluids. Please remember that the clean oil reservoirs of the machine should be purged of DEXRON®-III and filled with DEXRON®-VI for testing, flushing or filling General Motors transmissions/transaxles.

DEXRON®-VI can be used in any proportion in past model vehicles equipped with an automatic transmission/transaxle in place of DEXRON®-III (i.e. topping off the fluid in the event of a repair or fluid change). DEXRON®-VI is also compatible with any former version of DEXRON® for use in automatic transmissions/transaxles.

DEXRON®-VI ATF

General Motors Powertrain has recently upgraded to DEXRON®-VI ATF with the start of 2006 vehicle production.

Current and prior models that had used DEXRON®-III must now only use DEXRON®-VI.

All 2006 and future models that use DEXRON®-VI are to be serviced with DEXRON®-VI fluid only.

DEXRON®-VI is an improvement over DEXRON®-III in the following areas:

DEXRON®-VI

Extended Factory Fill For Life

160,000 km (100,000 mi) For Cars and Light Duty Trucks*

80,000 km (50,000 mi) (Severe Use) For Cars and Light Duty Trucks*

Clutch Friction Stability

Improved 100%

Clutch Durability Due To Fluid

Improved 120%

Oil Film Thickness

Increased 20%

Fluid Oxidation

Improved 100%

Foam/Aeration

Improved 150%

Shear Stability

Improved 200%

* These ATF change intervals remain the same as DEXRON®-III for the time being.

2006-2007 Transmission Fill and Cooler Flushing

Some new applications of the 6L80 six speed transmission will require the use of the J 45096 - Flushing and Flow Tester to accomplish transmission fluid fill. It is highly recommended that the clean oil reservoir of the machine be purged of DEXRON®-III and filled with DEXRON®-VI

Parts Information

Part Number

Description

88861003 (US)

DEXRON®-VI Auto Trans Fluid (1 qt bottle)

88861045 (US)

DEXRON®-VI Auto Trans Fluid (1 gal bottle)

88861046 (US)

DEXRON®-VI Auto Trans Fluid (55 gal drum)

88861004 (Canada)

DEXRON®-VI Auto Trans Fluid (1L bottle)

88861043 (Canada)

DEXRON®-VI Auto Trans Fluid (4L bottle)

88861044 (Canada)

DEXRON®-VI Auto Trans Fluid (205L drum)

[KHE]

The bulletin says to purge the oil reservoirs on the flush machines - is Dexron VI not compatable with Dexron III? Usually the new version of Dexron is compatable with the previous version.

[BodybyFisher]

I thought that was odd too Kevin, especially after they made this statement:

DEXRON®-VI is also compatible with any former version of DEXRON® for use in automatic transmissions/transaxles.

I would have liked to try the Dexron VI, but its too expensive, maybe I will use it over time. However if tranny synthetic finds leaks like engine oil synthetic, I would not be happy.

[KHE]

I don't know if the Dex-6 is synthetic or not??? The price would suggest that is synthetic but who knows? As long as Dex-3 is available, that's what I'll use until I get a car that requires Dex-6... Was there a Dexron 4 or Dexron 5?????

[JimD]

I don't know if the Dex-6 is synthetic or not??? The price would suggest that is synthetic but who knows? As long as Dex-3 is available, that's what I'll use until I get a car that requires Dex-6... Was there a Dexron 4 or Dexron 5?????

Dexron III will be disappearing from the shelves before we elect a new Pesident. If you have the storage space and want to save a few future dollars, I would recommend buying a supply of Dexron III for future needs. I plan to.

This link is only one of many I have seen since the introduction of the 2006 model year vehicles; if gm.com can't get it right, we are all in deep doo-doo. http://www.gm.com/automotive/gmpowertrain/...ease_31MY07.doc

Everything I have read indicates VI is a blended oil.

I can't locate the articles now but I have seen a few comments on the specifications numbering. Dexron IV and Dexron V products never made it to the licensing stage as the requirements for the new transmissions changed several times. And, the backward compatiblity requirement HAD to be met because Dexron III licenses were scheduled to expire.

[Ranger]

I don't get it. Sounds like Dexron VI is as good and better than DexronIII. Why stock up on III if VI will work in our cars? What am I missing?

[JimD]

Price maybe.

[Ranger]

Ah, OK thanks Jim. Now I understand what you were saying.

[BodybyFisher]

I don't know where I got the idea that it was synthetic, but here is an interesting article:

http://www.gm.com/company/gmability/enviro...uid_040105.html

[BodybyFisher]

Now I know where I got synthetic. I went to Pep Boys and bought a quart of Castrol Dexron VI ($5.99 a quart) for the purposes of researching it for my tranny refill, and looked it up on their site, see this:

http://www.castrol.com/castrol/sectiongene...ntentId=7028225