Antifreeze/Coolant evaporating/burning off?
I put the recommended amount of anti-freeze into the truck, and about 2-4k miles later, it's just all the old brown junk left.
I notice no leakage, and the top hose is brand new, although stiff and jerry rigged.
But I had this problem prior to the new hose installation.
I've tried the 100% mix and 50/50, while the 100% seems to last a bit longer, it is still being drunk by the gremlin.