Headed out for a trip at 5am tomorrow and happened to notice the coolant level was a little low. I figured I would due diligance and top it off tomorrow morning before I pull out on the 1200 mile round trip drive. I have an unopen gallon of O'Reilly coolant from another vehicle sitting in the garage. It is a 50/50 mix, but not sure if it will fly in the Disco's. You guys are the pros. Whatever is in it now is pink/red, if this wont work, what should I add to it?

 

Distilled water. Just to top up you won't change % very much. Don't want to chance mixing incompatible coolants. If you diluted it from 50:50 to 40:60, the freezing point would change from -36F to -13F. So you may not encounter such temps.

 

When was the last time you checked the coolant level, have you had to add any recently? I would suggest you do a pressure test to make sure you don't have a leak, cause on a 1200 mile drive you could toast that engine by allowing the level to drop to low while driving.