Dexron III vs Dexron VI

[DOCDRS]

Curious as to what engine nut has to say about this or anyone else?


dexron VI is supposed to be new and improved dexron III. GM TSB states that current and prior automatic transmission models that had used DEXRON III must now only use DEXRON VI
oil film thickness increased by 20%
foam /aeration improved 150%
shear stability improved 200 %
fluid oxidation improved 100%
__________________

[DOCDRS]

anybody going to chime in?

[kaneboats]

I thought it was backward compatible. This thread seems to indicate it is backward compatible with Dexron III and older fluids. Some posters claim lower temps in the transmissions as well. It also says it's a partial synthetic blend.

http://www.gminsidenews.com/forums/f53/dexron-vi-6-a-64757/

[driven sydeways]

yes, its backwards compatible in all vehicles requiring dex III, and it is a better fluid as DOCDRS showed. my automatic transmission teacher runs it in all of his GM vehicles, new and old. as far as use in the boat i would imagine it would be the same or better.

[Aquaholic]

If I change the fluid. Can I use my Oil-extractor pump? How many quarts do you think it will take to refill the tranny?

[Razzman]

I just did mine a week ago. You can use your extractor no problem. It won't get it all though. Manual says 2 quarts but go easy and keep checking after 1.5qts otherwise you'll over fill.

[DOCDRS]

If you have a vdrive, or can feel the 2 bolts on the underside of the tranny , drop the screen cover plate and you'll get another pint out of the tranny( but get something to catch it) and or remove completely to service the screen as well....there is a how too in the how to section

[zabooda]

I went to get some tranny fluid and the Castrol Dex/Merc ATF says on the back "Do not use this ATF in applications calling for Dextron-VI." So if you have a system that uses Dex6 then it is not backwards compatible.

[DOCDRS]

I went to get some tranny fluid and the Castrol Dex/Merc ATF says on the back "Do not use this ATF in applications calling for Dextron-VI." So if you have a system that uses Dex6 then it is not backwards compatible.

dexron VI is backward compatible in systems that use dexronIII/merc.....dexronIII/merc is not forward compatible in dexronVI systems

[kaneboats]

Well said. People confuse this all the time.

[zabooda]

Thanks DOC for correcting me. My brain must have been working in reverse that day.