O'reilly Dexron VI

Mar 18, 2021
So I have a 03 S10 4.3 125,000 miles, transmission fluid may or may not have been changed in it's life, it still has a red/pink color to it and does not smell burned and drives great.

I was going to go with Valvoline Dex/Merc (Dexron III) but I do not know the history of the vehicle on if it has been serviced before and if so which fluid was used so I figured I would go with the GM recommended Dexron VI just in case it has been serviced before and they ended up using that.

O'reilly's sells their brand which also claims to be used where Dexron II, III, VI, Toyota WS, Toyota T-IV is specified it also says it is "officially licensed and GM approved Dexron VI"

So has anyone had good luck with O'reilly's Dexron VI and what about in older higher mileage 4L60E transmissions like mine for a simple filter change and drain/fill?
Nov 13, 2020
I personally have used and recommend the Valvoline Maxlife DexIV. I’ve used it in my 04 Silverado with success. Walmart it used to be 18 bucks.
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Apr 25, 2017
it also says it is "officially licensed and GM approved Dexron VI"
Licensed means that GM themselves have approved the fluid and that it meets their requirement/spec 100%. It can't get any better than that. It's 100% as good as the ATF you would buy directly from a GM dealer.