Kevin pretty much summed it up. Stuff like ATF is also a cleaner of sorts 'cause the additive package will soak up a fair amount of carbon.
I recently talked to a guy from US Ordnance and he said a little TW25 mixed with the appropriate weight synthetic motor oil for the operating temp would keep a heavy machine gun in working order longer than most anything else.
We figured out decades ago that ATF, with a little STP in high wear areas, would keep an M60 running longer than anything else.
The only new thing out there that just might actually be revolutionary is Fireclean. Gotta get me some.
