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Discussion Starter #1 (Edited)
Just had the trans fluid and filter changed. My receipt showed III/ Mercon ATF in the parts section. I asked the guy at the counter why they didn't use Dexron VI like the owners manual says and he said its the same stuff. Is this correct?? I think this is an older fluid not for the newer transmissions requiring Dex VI

Any info???
 

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Did you have this work done at a GM Dealer, or just a regular repair shop?

You can use DexVI in a vehicle that takes DexIII. However, using DexIII in a vehical that takes DexVI is not a good idea. I'll check at work tomorrow morning on what your vehicle takes.
 

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Discussion Starter #5
Per the owners Manuel, it takes dexron VI. Work was not done at the dealer. They didn't flush and replace ALL the fluid, just drop the pan and replace filter and 5 quarts. I dont like the idea of having 2 different fluids in there, especially one that isn't listed in the manual.

I just want to make sure III/ Mercon is not the same thing as dexron VI before I ask him to replace all the fluid with the correct stuff (at his expense hopefully)
 

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I did search and came up with following Information....Re-gaurding....DexronIII Vs DexrionVI,

DEXRON-VI was Introduced in 2005"....According to the DEXRON-VI ...."DEXRON-VI....Replaces..DEXRON-III,

......According to General Motors DEXRON-VI Global Service-Fill Specification, "earlier type fluids are Not forward compatible with Transmission hardware that was designed to use DEXRON-VI fluid, i.e. DEXRON-III is Not compatible with the most recently designed Transmissions, and the use of these earlier type fluids could result in Transmission Damage.

.....All current calibrations and certification tests are now conducted with DEXRON-VI ATF......... DEXRON-III fluids Should Not be used for these applications where the Owners Manual Recommends the use of DEXRON-VI.

Below is the rest of the Information....on Dexron,
http://en.wikipedia.org/wiki/DEXRON#cite_note-gmsite
 

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Dexron III Should not be used in your vehicle. I'd go back and have them replace everything with Dex VI. I'm positive you truck takes DexVI.

Like I said before, DexVI can be used in any GM vehicle where DexIII was recommend. My truck for example can use DexVI or DexIII. I have Mobil 1 Dex VI in my transmission and transfercase. DexVI meets DexIII, but DexIII does not meet DexVI

With your truck, DexIII can not be used.
 

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Go back and make 'em change it to Dexron VI.
 

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Discussion Starter #9
Got it taken care of today. They flushed out the old and replaced with 12 quarts of Dex VI for no charge.

Thanks for the info!
 

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Good to here you got it taken care of. Must be a decent shop if they owned up to there mistake and corrected it.
 
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