Dex VI or Dex III/Mercon in '93 4L80E?

[bullwinkle]

For the C3500 in my sig, going to do a pan drop (& cooler line change), has anyone used Dexron VI in an older 4L80E before? It has been flushed in the past when I first got the truck, has a B&M aluminum pan & an external cooler, has 148K.

 

[barkingspider]

What is oem fluid? It's it's dex3, then dex6 will work like normal.

 

[Oil Changer]

Dex VI. Backwards compatible. Excellent fluid. What was it flushed with? If Dex VI, skip the line exchange.

 

[bullwinkle]

It was flushed with Dex III. I'm just wondering if anybody's used Dex VI in an older 4L80E-it would be nice to have the additional high temperature protection of the newer syn ATF.

 

[901Memphis]

DexronVI is a superior spec in every way to a mineral DexronIII, I have seen many people use DexronVI in these transmissions as it's the correct fluid now.

If you haven't seen this take a look.

http://www.bobistheoilguy.com/forums/ubb...er_#Post3014880

 

[crazyoildude]

i am partial to max life atf and think that is a syn blend but not 100% sure on that

 

[147_Grain]

Maxlife ATF is most likely a Group III highly refined synthetic.

 

[901Memphis]

Maxlife is definitely more of a synthetic than DexronVI but both are light years ahead of mineral based DexronIII. While DexronVI most certainly uses Group 3 base oils the Maxlife has a better chance of using real synthetic blend with the group 3 based on Maxlifes superior shear stability compared to DexronVI.

We also know that Lubrizol provides the PI package for Maxlife which says a lot about how serious Ashland is with this products performance.

While it's impossible to know the exact base oil composition of Maxlife since it's proprietary, the shear stability is a good indication of quality.

 

[Georgiey22]

I'm personally running Valvoline Dex/Merc Max Life in my 1999 5.3L Silverado 1500. I've had it in the transmission for 2K miles and the truck really likes it. Shifts are crisp and smooth. At this point I'm going to exclusively run this in my truck and will be doing a drain/refill every 15K miles because I enjoy working on my truck, it's fun!! Max Life fan boy here.