Fuel Mileage

[canadian brickie]

Newbie to this fourm looking for feedback on mileage. Just purchased a 2008 F450 King Ranch loving the truck not the mileage, just pulled my 35 foot Jayco from Canada to Florida (first time on this truck) had a 2004 F350 before the 450. the mileage while I ran in stock for a tank was 6.3 MPG tuned to tow safe with edge evolution and improved milage to 6.7 MPG. The engine load was less with the edge tune but the 1350 EGT alert went off on hills. Any feedback would be appreciated. What would be dangerous EGT level for how long?
Thanks

[wingnut60]

Can't help with the EGTs--does your truck have the 4.88 or 4.30 axles? If the 4.88, the mileage won't get much better.
My '09 w/4.30s get 12.5-13.0 solo and 8-9 pulling 17000 lb fifth wheel.
Joe

[canadian brickie]

Not sure on the rear gears trying to get the build list from my local ford parts guy.

[f450bronco]

on my 450 i have 70000 miles and am getting 9-10 mpg on the city and 12.5-13.6 on the highway

[canadian brickie]

Thanks I've read around the fourm a bit and seeing that the mileage is what it is, we have a clean air inspection so got to keep it stock no mess'n with the exhaust Best pulling truck I've had yet!