mark5w

Average miles per gallon on two RV trips: 11.0 (corrected see post below) About 425 miles of combination of back roads, stop light 4 laners and open 4 laners.
Better than I expected.
F150 SCREW
3.5 Twin Turbo
6.5' bed
3.75 rear
5215 miles
18" wheels
PullRite Superslide
5th Wheel
Crossroads Patriot 335SS
9600 lbs.

Buck50HD

I thought the good mileage may have been a coincidence but we have completed a few more trips (1600 total miles) with the 5th resulting in a range of 9.6 to 11.8 MPG. The 9.6 happened once at 25F-34F air temp with 10-15mph headwind. The next lowest was 9.8 with a 10-20MPH headwind. The 11.8MPG happened with 5-15mph quartering tailwind. No wind or light crosswind continues to be around 10.5-11. Can't quite compete with Mark5w but this rig is awesome

Details are in the sig. Truck just turned 12k miles. BTW, mileage hasn't changed a bit since day 1. Still gets 20-22 empty and <65MPH.

mark5w

Buck50HD
Forgot to calculate in the trip home last October when I picked up the Cruiser.. then I only got about 9.9 driving home at night in the rain. (about 82 miles) So that brings it down to 11mpg.

Buck50HD

Regardless, 11 is still really good. Seems to be a trend with ecos and the more aerodynamic 5th wheels getting close to 11mpg. Many will blow off 1 MPG difference while towing but that's the same cost savings as getting 4 MPG better with an unloaded truck over the same distance. Something to think about.

jcain

Total trip avg (15.3mpg) 600 miles into my Vegas to Kansas move. TT weighed in at 7680 this morning by itself, truck was 9810 with full tank and trailer hooked and wd'd.

Buck50HD

That is impressive pulling a TT. If that is the norm in flat, no wind conditions, the diesel is paying for itself. Too bad it's not emissions compliant or stock. Over on RV.net, the stock diesels don't seem to get near that good. Seems like 11-13 with a 5th like mine is typical, so 1-1.5 better.

Also just noticed that your TT is not even 10' high while my 5th is 12'.

jcain

My 10' high is bucked from the bed rail height. Your 12' is off the cab top

Buck50HD

Frontal area with a TT or 5th is dictated by largest area, which is the trailer. The drag coefficient may be affected by the gap between the cab and TT (or lack of gap with a 5th) but that doesn't change the frontal area term in the drag equation.

jcain

The coefficient of drag is the area forced to oppose frontal advancement. I'm betting you dollars to cents that most TTs have a bigger frontal area touching wind,

Adventurer

Took 2012 3.5L F150 Platinum Ecoboost V6 out for first tow with new 5000 lb. 24' long travel trailer one week ago. Went from sea level to 7000' with lots of curves, then back another way up to 8400' feet at first and back to sea level. Got 10.7 mpg. Have about only 4000 miles on truck.