Originally Posted by SirTanon
...assuming that Greenbrier even does THAT. My guess would be they buy the oil in bulk, pre-formulated, from someone else, and then re-bottle it in these containers, at an overall cost well below the $1.00/pint mark.
"Greenbriar" is just the name that Dollar Tree puts at the distributor for all of their house branded stuff. That address is Dollar Tree headquarters.
https://goo.gl/maps/jxw6UiRgXs12
https://www.smandf.com/portfolio/dollar-tree-headqtrs-expansion
They have absolutely no manufacturing of their own; they just have someone else make it for them. Same as Autozone, Napa, O'Reilly, Carquest, Walmart, etc. It might not be a big producer, but definitely made for them by someone else. Could very well be a blender buying a matched additive package and base oil as suggested. I'm kind of cheap and have bought stuff at Dollar Tree before, and I've seen their boxes with the address in Chesapeake, VA where the whole thing was clearly made and packaged in China.
I do remember when Target used to sell Car and Driver brand motor oil and parts. Held a bottle right up to Valvoline and I'm pretty sure if was made for them on the same production lines. They had a very unique printing for the production codes.