Marztian

Grumpy, I’m an AMSOIL guy. I do believe that their products are awesome, I’ve used them in many applications and always been happy with the results. I advocate for their products to friends and coworkers. I do think they’re superior. In the present case, this point is the reason for not using AMSOIL: AMSOIL doesn’t have DEX VI specific fluid - sure it may meet those reqs, but I agree with dvzzz and his statement regarding the one-for-all approach. The additives are really the differing factor. In an attempt to make the fluid better for most vehicles, I’d hope it doesn’t create a negative for the 6L80. Transmission fluid differs, as it should, depending on the components/product it interacts with. Truthfully, AMSOIL could be the BEST thing I could ever put in my transmission. But, I do want to be sure of it, I don’t want thousands lost to a transmission, and I don’t know how concrete AMSOIL’s warranty to that is. So for this time, I went with the Dex VI ACD. Next time, I may very well go AMSOIL. Given a longer timeframe, I may build confidence to the AMSOIL ATF. Also grumpy, I agree to the bullshit high heat of these 6L80s. Would you suggest a thermostat delete? I have gotten up to 230°F or so on occasion towing 10k through mountains...

So, went to drop off the truck this morning. Told the owner that although he mentioned using a Dex IV instead of AMSOIL, I didn’t have the time or motivation to go get any, so I have the AMSOIL. His face dropped and he said he would use it, but really doesn’t want me to be stuck with a transmission replacement bill, as he wouldn’t warranty the change himself if using AMSOIL. He said it seems like the finer compounds in AMSOIL’s ATF get into the electronics and cause failure/issues. I’m thinking this is the approach of my transmission guy. He knew a hell of a lot about the 6L80, and knows this industry VERY well. I think his grievance with AMSOIL is that although it may be Dex VI compliant, it’s not nearly the same. Also, my father who works on multi-million dollar mining trucks control modules referenced the insane amount of R&D he does for coatings and fluids near their control mods. The slightest change can reduce longevity exponentially. So, he is the one that suggested getting my own fluids, because I could probably get them for cheaper at retail, with deals going on. He expected me to bring my steak... but when I thought I was bringing prime rib, he told me it was an awful grade cut. ? Essentially this guy said he has had to replace a lot of the 6 speeds potentially due to AMSOIL, a lot of the 8 speeds because..... I think we all know their issues. And in the end, I’m going to be selling this AMSOIL, and I went with his ACDelco for $6.98/qt and he’s giving me a good deal on the change. All in all, the guy is VERY honest and I believe he is acting in my best interest. He’s a transmission guy and knows the products and outcomes well, I’m inclined to believe him. It’s not to say that for a different transmission, it’s not a great option. I also don’t know better, which is why I reached out here. For all those interested, though, this is what I did and why. Thanks for all the input!

I had purchased AMSOIL Signature Series ATF for my 18 Silverado - 6 speed. After having it sit for a while and never getting to a transmission flush on my own time, I called a local, honest, reputable transmission shop near me that has always treated my dad very well. They’re a no-bull, honest shop, and the owner is down to earth and knowledgeable regarding transmissions, as he should be. I informed him I had AMSOIL and wanted it switched with that, and he advised that for the 6L80E, it wasn’t a great idea. He has nothing against a better fluid, but he advised that AMSOIL doesn’t treat the electronics nicely, and it’s a common issue. I’m an AMSOIL guy, and do want him to use the AMSOIL fluid, but has anyone else heard of this or advise to simply use DEXRON VI and NOT AMSOIL?