6.7 Diesel Fuel/Water Separator Draining

[seahunter]

Hello,

My owner's manual states to drain the fuel water separator when the computer indicates it is time. I know the frequency would vary depending on fuel used, but I cannot find anywhere in the manual an approximate mileage for draining it. I have 5,000 miles on the truck now, with one oil change but have never drained the separator. I do not know if they drained it at the oil change - would that be normal? Is 5,000 miles a lot without having to drain the water separator? Engine seems to be running fine. I get about 17-18 mpg without trailer, and about 11-12 towing.

Thanks for any help.