Anyone use Dex 6 in 4l80 and have high miles on it?

[DONWATERS]

I have been considering switching to dex 6 in my 97 gmc 454 4l80. Anyone use dex 6 in theirs with positive or negative results? I change the fluid about every 15k with dex 3.

 

[Chris142]

We have the smaller 4l60 in our Tahoe. I serviced it with dex6 @90k and again @180k. Not any weird stuff in the pan or stuck to the magnet @180k.

I'm sold.

 

[Bud_One]

Our 2005 Chevy Silverado 2500HD 6.0 with the 4L80E .
I've done a flush at 100k miles and a pan drop drain and fill / filter change at 129K miles both with Dexron VI , vehicle currently has 145,409 miles on it.
I've towed a U-haul carhauler with a 1992 Ford F150 Reg cab truck on it 350 miles and taken a couple of trips to Atlanta, GA with it.
I've have had no issues with the trans.

 

[clinebarger]

The 2006 & up 4L80E's came with Dexron VI as factory fill.....Use with confidence!

 

[PiperOne]

We have a 4L85E (the 4L80 with the bigger planetary gears) that uses Dex6 and has over 450,000 miles on it....flawlessly. All Dex6 is not created equal though..and it isn't all Full Syn either. Originally we used the Delco branded stuff and oil samples showed it was shearing away some viscosity with use (and there isn't much to begin with lol).Tuirns out it's a blend at best. So we switched to a Full Syn (Chevron/Havoline) and everything held up better. Service interval is 40,000 miles although it has been pushed out to 60k now and again and the oil seems to hold up. Unit is a 09 Duramax powered cutaway van chassis with a fiberglass freight body on it. Been in service since late 2011.

 

[rubberchicken]

My 1997 454 4x4 Suburban has Dexron 6- works fine.

 

[SteveSRT8]

We still have one 4L80E in service in a 3500 chassis that weighs a tick over 9k pounds every day of its life.

203k miles and still running great. Always used Dex VI with zero issues.

 

[Jimzz]

As said use it without worrying. You can even use Valvoline maxlife as well.

Unless you are burning the fluid up by over towing, doing burn outs, etc... I would extend it to 30k with a good synthetic trans fluid.

 

[WyrTwister]

Our 2006 Buick Lacrosse 3.8i used Dex 6 .

 

[Gimpy1]

From what I researched and read DEX3 is no longer licensed by GM. DEX 6 is the new standard and is backwards compatible for use in automatic transmissions. That being said, this summer I flushed my GTO's and replaced the old Dex 3 with Castrol Dex6, and have had 0 issues.

 

[dave1251]

Originally Posted by PiperOne
We have a 4L85E (the 4L80 with the bigger planetary gears) that uses Dex6 and has over 450,000 miles on it....flawlessly. All Dex6 is not created equal though..and it isn't all Full Syn either. Originally we used the Delco branded stuff and oil samples showed it was shearing away some viscosity with use (and there isn't much to begin with lol).Tuirns out it's a blend at best. So we switched to a Full Syn (Chevron/Havoline) and everything held up better. Service interval is 40,000 miles although it has been pushed out to 60k now and again and the oil seems to hold up. Unit is a 09 Duramax powered cutaway van chassis with a fiberglass freight body on it. Been in service since late 2011.



It's full synthetic it's a blend of Group III/IV/V base oils.

 

[wtd]

I'm running Supertech HM Automatic transmission fluid that is Dextron III compatible in the 4L80E in my 1998 Chevrolet K3500. After trying Mobil 1 full synthetic transmission fluid in the 4L60E in my 1998 K1500 back when it was fairly new and it causing the transmission to slip, I've been leery of trying a full synthetic tranny fluid in this year of Chevrolet truck again.

Since some of you are using Dextron VI in this generation of truck with good results, I may give it a try.