Dex VI sux.......

[AlisoBob]

Dex VI is a terrible fluid that induces T/C shudder thru it's hygroscopic defects.

EVERY GM car I own get's the Mobil 1 Blue Label.

My new to me 2015 2SS automatic had very lazy shift behavior. Granted, the fluid did have 58k on the clock.

After a double drain and refill with the Mobil 1 Blue Label..... It feels SO MUCH BETTER. Like a shift kit was installed? No. But a big improvement in shift quality and strategy.

[el ess A]

I guess I got lucky and had a good batch. I've never had an issue running the VI. But it's replaceable. Do what you must.

[AlisoBob]

Originally Posted by el ess A

I've never had an issue running the VI. Do what you must.

Google "GM Torque Converter Shudder" to educate yourself. It's a huge issue across every GM platform from Minivans to Duramax Sliverado's and it's all traceable back to Dex VI

[el ess A]

When the TSB came out, I was under the impression that the 2016 and up had the "issues".

I don't recall that issue as a wide-spread problem with the 5th gens. Haven't had any issues in the 2010 with any shudder or shifting issues. At least not yet. Stuff is about thin as water, though, right out of the bottle. So if your transmission isn't spot on with clearances, there could be some issues, I suppose.

[Ashen 6.2]

Originally Posted by el ess A

When the TSB came out, I was under the impression that the 2016 and up had the "issues".

I don't recall that issue as a wide-spread problem with the 5th gens. Haven't had any issues in the 2010 with any shudder or shifting issues. At least not yet. Stuff is about thin as water, though, right out of the bottle. So if your transmission isn't spot on with clearances, there could be some issues, I suppose.

Same here. I had the shudder issue in my 16 GMC with the 8L80 trans and that Blue label fluid helped a ton. But for the 6L80, nothing but AC Delco 10-9243 synthetic Dex VI.

[Infidel67]

See, this is crazy confusing, I got 110k on mine and already ordered the Red Line 30505 D4 Synthetic Automatic Transmission Fluid (ATF) for my M6.
Some say do some say don't.

[el ess A]

Originally Posted by Infidel67

See, this is crazy confusing, I got 110k on mine and already ordered the Red Line 30505 D4 Synthetic Automatic Transmission Fluid (ATF) for my M6.
Some say do some say don't.

What's confusing about this? You have an M6. TC shudder isn't a problem with a 3-pedal, since, well, they don't have one.

A bit off-topic since we were talking automatic transmissions here, but several people have went to the Redline in the past with mostly fine reviews for their M6. The GM fluid that came in your M6 originally is just a modified Dex III mixture (that you shouldn't put in an older automatic transmission).

And you DON'T want to use Dex VI in your M6. I personally use Mobil 1 Multi-vehicle ATF in the ZL1's M6 and it's been perfectly fine. And <10 bucks/quart at Summit.

[Infidel67]

Thanks for clarifying el ess. I'm just a N00b still learning about Car Engines lol.