First trailer towing evaulation and obseervations
 

Lariat Screw FX4 (3.5 Eco/3.31 rear axle ratio, BFG A/T KO2-275/65 R18 off-road tires, Fuel Assault wheels - towed weight of Scamp trailer and cargo 2900 #). I Just got home from our 4500-mile, two week trip to Utah from Illinois. This was my first trip towing my trailer and I was surprised how well the baby V-6 handled the trip. I have always used 87 octane fuel and my non-towing mpg ranges between 17.5 and 19.5 mpg. All of my previous trips were short, less than 150 miles, and I was happy with the mileage as my previous Utah tow vehicle was a 2010 Raptor which got 12 mpg on a good day. Reading the towing section in the owner’s manual it suggested that when towing to use premium fuel so I thought I would try it. I ran a tank of premium thru the truck before we left then used it on our trip. I averaged 15.9-16.4 towing on the first two fill-ups. I needed gas in Hays KS and the Shell station was out of premium so I got 29.8 gallons of regular, 87 octane gas. My mileage instantly dropped to 12.1 mpg and it took 2 fill-ups to get back to 15 + mpg and I averaged ~16 mpg towing for the rest of the trip. BTW while not a great off-road truck it did ok on some of the milder Utah backcountry trails. TM

Yeah I notice about 3-4 mpg better towing with 91 or 94 if I could find it. It really helps the 5.0 in the mountain altitude. Were u using tow/haul mode?

Yes, tow haul mode except in western Kansas, no hills. Drove 70 mph on the interstates and 60-65 thru Colorado on Highway 50. Truck did great in the mountains but I did shift into manual on some of the downgrades going over Monarch Pass, tow haul kept downshifting to 2nd, so I would select manual and shift into 3rd. Very happy with the performance of the Eco. I only had 2900 miles on the truck when I left home, and I changed the oil to Mobil 1 before the trip.

No scientifically-derived numbers, but I have enough towing miles on my EcoBoost drivetrain that I'm sure the improved MPG with 91-octane premium gas for towing more than pays for the higher cost of premium. Plus the engine purrs nicely when running on premium. ;)

Sucks you couldn't get the right fuel in Hays. Glad you are happy with how it towed.

just curious are you using semi-synth or synthetic oil?

full synthetic Mobil one, I have used Mobil One in all of my trucks and cars since 1989

Thanks for the write up. I love Moab. I went mountain biking out there in 01 and have wanted to go back ever since.

Curious as to why you elected to ditch tow/haul in KS? I know it's flat (not really) but it doesn't lock out the highest gear in these trucks like it does in others. I found that it simply altered the shift points and prevented a lot of downshifts on climbs.

Sorry for the late response, been out of town. I have to admit that when we stopped at a rest area in KS to let the dog do her business, I forgot to select tow/haul when we left and did not notice it until I got to Colorado. I didn't notice any difference in towing.

You shouldn't notice any difference when towing on the flats of western Kansas and eastern Colorado. But when you hit the foothills of the Front Range the tow/haul mode comes alive, especially when comin' down the mountain.