Anyone Using Dextron VI Fluid? (Page 1/1)
Dennis LaGrua NOV 08, 10:14 PM
Since my drag racing days I've always favored running an automatic transmission. I am now about to refill a rebuilt 4T60e on a 4.9L swap and was advised to use Dextron VI transmission fluid. GM advises that it is backwards compatible with all prior Dextron II and III automatic fluids. Dextron VI is a synthetic fluid that is supposed to function better under heat, last longer, is more viscous and will provide better shifts and smoother operation. Any user reports out there on any Fiero auto applications or with swapped 4T60e. 4t65e , 4T65eHD transmissions?

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

ericjon262 NOV 09, 12:00 AM
I have it in my 700R4 equipped 4x4 Suburban, shifts fine, nothing noticable to me, I don't baby it, but I also don't abuse it, kinda hard to abuse a transmission with 165 wheezing TBI HP.

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"I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."

cognita semper

1Packrat NOV 09, 08:58 AM
Used IV in my 4t60 swap works fine. The only thing I don't like with IV is even though it looks red when you pour it in when you pull the stick it is clear as water. This makes checking the level very hard. Resorted to touching the stick to a paper towel to see the wet mark of the level.
Dennis LaGrua NOV 09, 07:02 PM

quote
Originally posted by 1Packrat:

Used IV in my 4t60 swap works fine. The only thing I don't like with IV is even though it looks red when you pour it in when you pull the stick it is clear as water. This makes checking the level very hard. Resorted to touching the stick to a paper towel to see the wet mark of the level.



Is that a typo? Dextron IV and VI fluids are different. I used Dexton IV (4) in my 3800SC/4T65eHD swap and its works well but the Dextron VI (6) is a synthetic fluid. I believe that's what we are referencing. If it is Dextron VI it should work better in Fiero trans swaps as most of them use the small transmission cooler in the Fiero radiator. While that works much of the time, Dextron VI and its superior heat tolerence may provide longer transmission life.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

theogre NOV 09, 07:30 PM
GM stopped Licensing Dextron III in 2011. Dextron II way before that. Use Dextron VI

Highlights of all Dexron trans oils...
https://en.wikipedia.org/wiki/DEXRON

Note: GM did re-release Dexron III in 2016 but only for some things, Not Automatic Trans.

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

Wichita NOV 09, 09:36 PM
I just recently replaced the 5-speed Isuzu transmission with Synchromesh. I believe that is what is recommended for manuals.
Dennis LaGrua NOV 10, 05:41 PM

quote
Originally posted by Wichita:

I just recently replaced the 5-speed Isuzu transmission with Synchromesh. I believe that is what is recommended for manuals.



I believe genuine GM transmission fluids are what should be used instead of the many clones which may or may not meet specs. The manual and auto fluids are different but the consensus is to use Dextron VI in the automatics. The AC Delco GM Original Equipment 10-4033 manual Transmission Fluid is what GM is now recommending for the manual transmissions. It may be better than Synchromesh but I have not read many user reports.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

Cajun NOV 11, 03:07 PM
I use Dextron VI the synthetic stuff in my swapped 4T60 with no issues.