There is no need for baseless fear mongering. DEXRON VI is the correct viscosity fluid for the OP's transmission.
Dex 3 or Dex 6
- Thread starter hardheaded
- Start date
It's engineering.....not "fear mongering." I'd expect better from BITOG.
The correct viscosity fluid for the OP's transmission is the one the factory engineers designed for it. Back-speccing a fluid
doesn't make it "the best one." You can't have both a 7.5 and 5.8 cSt (LV) fluid both being optimum. It's one or the other.
The marketing dept's of major auto makers have back-specced a lot of motor oil and trans fluids since approx 2000 for improved
mileage (reduced friction)......it doesn't mean those are optimum for the engine and transmission life. They are apparently "good enough"
for mfg warranty life.
For a complete answer to the OP's question we need to know what year that trans was built (in new vehicles from 1993-2012), and the current
rebuild specs. Back-speccing from Dex III to Dex VI on the 4L60 was done in 2005. "No longer licensed" doesn't mean "obsolete." GM initially tried to back spec the manual T56's to Dex VI and realized that "slightly lower viscosity" was a problem. So those cars are still specced for a
Dex III-type fluid.
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Manual transmissions or transfer case applications aren't the same as an automatic transmission, just because Dex VI doesn't work in those applications doesn't mean that it doesn't supersede DEX III in automatic transmission applications, those are completely different applications, if DEX VI caused massive problems in older design automatic transmissions they'd have never puled the DEX III license and they'd have pulled the back spec.
Correct. Such confusion on this subject.
I put Dex VI in my automatic transmission that spec's Dex III and it definitely shifts better. I'm also not easy on it at all. I change the fluid frequently so it's not like I replaced 300000 mile fluid and noticed a difference. This is a transmission that usually gets once a year changes.
The owners manual of my old 2006 Silverado with a 4L60E specifies Dexron VI. In fact, I recently dropped the trans pan, installed a new filter, cleaned the magnets and and pan and filled with new Valvoline Dex VI licensed fluid. All is good.
Dexron VI is the superior fluid. Use it with confidence.
Dexron VI is the superior fluid. Use it with confidence.
Valvoline also sells their Import Full Synthetic ATF which is a DEXIII type fluid for non LV transmissions. Cst is 6.9 @operating temp. This is my preferred ATF for anything that came from the factory with a thicker fluid.
