My '06 with the 6 speed Allison is calling out Dexron VI ATF.

Is this dealer-only at this point in time? If so, does anyone know if Mobil has any plans to bring their synth up to this spec?

Are you sure that's not Dextron IV?

Go with what Allison recommends, they are the ones that made it. Yes GM can screw you out of any warranty work at any time they feel like it.

Are you sure that's not Dextron IV?
Unless it's a misprint in the Duramax supplement for the owner's manual, it's a "VI"

Huh, never heard of it. Same thing happened when Chrysler came out with their new ATF+4 a couple years ago. In less than a year everyone will carry it. Oh, and just FYI, you may get more responses if you have a mod move this to the auto tranny section.

In less than a year everyone will carry it.
I dunno.... there are still no approved substitutes for Toyota type T4 or WS, and T4 has been around for years.
Amsoil claims that it's good to go, but Mobil specifically states that it is incompatible.

Use ...

Unless it's a misprint in the Duramax supplement for the owner's manual, it's a "VI"

You're probaby right... I talked to a transmission tech the other day who said that a GM guy told the class he was attending to use Dex VI if they do any work on an Allison and don't want it back for warranty work. He assumes that Dextron VI is fully synthetic ATF. His comment was the Dino ATF will get them thru the warranty period and that's all they need.

I'm switching over to Amsoil Torque Drive ATF.

Use ...
Checked on the link (bought a Fumoto and 10 pack of the plastic fender clips), but couldn't find anything spec'd to Dex-VI.
Is Dex-VI simply a formal endorsement of synth fluid, meaning that Amsoil, Mobil-1, and Schaffer are fine?
I checked the LDS today and the parts guy got a funny look on his face as he said "oh frack" as he confirmed in his computer that Dex-VI was indeed spec'd for my tranny, and that he has never seen bottled VI.

He swears that the techs have it in bulk... but given some comments similar to CaliDMax's, I'm concerned that the delarship might just be pumping Dex3.

I'm getting ready to do my first oil change tomorrow (nearly 2k)... gonna' use Rotella 15w-40. I'll switch to a synth 15w-40 for the next change and stick with that from there on out. I'd like to swap the trans filter tomorrow as well, but I don't want to short the tranny the pint or so that the filter holds.
I'll try a different stealership tomorrow morning, if not, I guess I'll let the tranny spin-on ride until I can get Dex-VI, even if it means that I'll be due for a drain/refill.

If I start getting close to 10k and still can't find the stuff, will I lose enough fluid to worry about by just swapping the spin-on dry? The tranny pan looks pretty big, so I assume it's got a fair sized reserve.

BTW: Why did this get moved to the 6spd manual forum? The '06 Allison automatic is 6spd...

ANYWAYS.... I heard some unsettling news from a local dealership today.

The '06 specs Dex-VI.
Retail Dex-VI has not shipped to the dealers yet (we knew that).

Apparently, BULK Dex VI has ALSO not shipped. The dealership where I bought my truck indicated that they had it in bulk only, but were not changing the Allison spin-on until 15k (even though the owner's manual says at the first oil change).
I called a different dealership. Parts girl said, ya, it's on order.
Sat on hold for a new minutes, she came back on the line.... "I checked with the service manager and he said to use regular dex, 'that's what we're using'"

Be careful guys... unless and until we find out if TranSynd, Amsoil, or Mobil-1 are okay with these new trannies, I'd be staying well clear of stealership service until you actually see bottles of Dex-VI sitting on the shelf in the parts department.

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