I have a friend with a 2004 6.0 with about 80K miles on it.
F350, automatic, 4x4 crew cab in stock trim other than an aftermarket intake/air cleaner housing and muffler delete.

Antifreeze has started disappearing at the rate of a gallon every two weeks.

No wet spots on the engine or under the truck.

Where or what should I tell him to look at or for?

I am at a total loss on Strokes, but I know where to ask questions to get good answers.

 

I'd say it's either the egr cooler (just had mine done) or one (or both) head gaskets.

 

Is he seeing any exhaust smoke or white deposits/residues splattered in various areas under the hood (particularly around the degas bottle)? Although the list of possible sources is long (below), it quite often boils down (pun intended) to what Lee said. What is he using to refill his coolant system with?

<TABLE style="WIDTH: 254pt; BORDER-COLLAPSE: collapse" cellSpacing=0 cellPadding=0 width=338 border=0 x:str><COLGROUP><COL style="WIDTH: 254pt; mso-width-source: userset; mso-width-alt: 12361" width=338><TBODY><TR style="HEIGHT: 12.75pt" height=17><TD class=xl24 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: windowtext 1pt solid; BORDER-LEFT: windowtext 1pt solid; WIDTH: 254pt; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" width=338 height=17>Possible Sources (from the manual)</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Coolant hoses or tubes</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Hose clamps</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Coolant pump O-ring seal or gasket</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Thermostat O-ring seal or gasket</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Thermostat housing</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Radiator</TD></TR><TR style="HEIGHT: 25.5pt" height=34><TD class=xl26 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; WIDTH: 254pt; BORDER-BOTTOM: #d4d0c8; HEIGHT: 25.5pt; BACKGROUND-COLOR: transparent" width=338 height=34>Transmission fluid cooler (in radiator) (if equipped)
(may leak internally or externally)</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Degas bottle</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Pressure relief cap</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Coolant pump leaking from weep hole</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Heater core</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Coolant crossover manifold assembly (if equipped)</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Engine gaskets (may leak internally or externally)</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Oil cooler (may leak internally or externally)</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Heated PCV fitting (if equipped)</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Cylinder block core plugs (if equipped)</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Cylinder head core plugs (if equipped)</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD class=xl25 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: #d4d0c8; HEIGHT: 12.75pt; BACKGROUND-COLOR: transparent" height=17>Block heater (if equipped)</TD></TR><TR style="HEIGHT: 13.5pt" height=18><TD class=xl27 style="BORDER-RIGHT: windowtext 1pt solid; BORDER-TOP: #d4d0c8; BORDER-LEFT: windowtext 1pt solid; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 13.5pt; BACKGROUND-COLOR: transparent" height=18>EGR cooler(s) (diesel only)</TD></TR></TBODY></TABLE>

 

If there is no puking out the degas bottle and no smoke out the exhaust. It is possible he is loosing that much through this orange hose on the EGR cooler, ford has an updated hose it's blue. Page 74: Unique Service Procedures

 

Thanks for the help, I got way to busy at work, sorry it took so long to get back and say thanks.

 

probablly blowing out the exhaust from the egr

 

check the egr and oil cooler before considering headgaskets lots of write ups for the diagnosis of a cooler or head gasket