djsr2015

So amsoil does have a 5w30 dexos D. I can’t imagine a slightly thicker oil would hurt engine. It has a block heater too, for those cold starts. Southern Ontario, Canada.

Thanks for all the helpful responses. It’s a lot to digest. I’m guessing at the very least I should stick with a dexos D certified oil just so I won’t void my warranty. Definitely want longevity of the engine, turbo and dpf though. i wouldn’t have thought twice about the oil weight, but a friend of mine enlightened me that in North America the manufacturers tend to run thinner oils for the slight advantage on mpg, where over in Europe and other parts of the world a thicker oil is run to provide better protection for the engine. does anyone know of anybody owning/operating a 3.0L duramax Europe or somewhere else in the world to confirm? I also didn’t realize how big of a brand Amsoil is. Total quartz is another brand I’m familiar with, they won’t have a dexos D formula until the first quarter of next year though. Interesting how amsoil has a dexos D to offer now, because I thought acdelco and exxonmobile had an exclusivity agreement on the recipe until the end of 2021.

2021 Sierra 3.0 owner. First truck. Just wondering if there would be any reason/advantage to use 5w30 dexos D oil instead of the 0w20 dexos D. had a ‘09 vw jetta tdi, and a 2018 cruze with the 1.6L diesel. I was surprised to see the 3.0L duramax called for 0w20. Just seems a little thin to me. would the thicker oil sacrifice some fuel economy but provide better engine protection without restricting oil flow to the turbo and other critical components? thanks.