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Towing mileage on 650 mile trip.

16K views 40 replies 27 participants last post by  Gator06 
#1 ·
I just towed my 24’ pontoon boat, 5,500 lbs., for 650 miles. I averaged 9.2 mpg while driving 75 mph. I was surprised that the mileage was that poor. When I hook on to my 28’ enclosed trailer that will weigh 13,000-14,000 lbs., I’m guessing it will be even worse. I’ll probably keep my speed around 65 mph with the 28’ trailer, to try and improve the mileage.
 
#38 ·
I have towed with a LML 2016 MY, 6.7L powerstroke 2017 MY, and will do our normal vacation tow in about a month with the 2019 L5P. From my experience towing and unload here are the results from around 85,000 miles accumulated between the trucks and motors. Keep in mind these are hand calculated numbers, and are generally numbers with regens going down the road.

Our fifth wheel weighs in at 14,200lbs, and usually double tow a 14ft utility trailer with a Honda Pioneer 1000-5 behind the fifth wheel... total weight is right at 17,000lbs.

Powerstroke 6.7L Unloaded: 75mph no wind best I ever saw was 17.4mpg, if you dropped speed down to 65mph with no wind I saw 18.5mpg consistently.
Powerstroke 6.7L Loaded with the above setup: I tow at 65mph, depending on wind obviously the best I saw was 9.5 mpg.

2016 LML Unloaded: 75mph no wind best I ever saw was 17.5mpg, if you dropped speed down to 65mph with no wind I saw 19.5mpg consistently.
2016 LML Loaded with the above setup: Towing at 65mph, depending on wind the best I saw was 10.2mpg.

2019 L5P Unloaded: 75mph no wind best I have seen so far is 19.5mpg, if you drop speed down to 65mph with no wind Im seeing 20.6mpg consistently.
2019 L5P Loaded: I'll update this after our trip.


The powerstroke is obviously the heaviest truck of the bunch and the mileage numbers show it.
 
#41 ·
I just drove from JAX to Asheville with my 06 LBZ towing 18k 5er and loaded truck. I avg 12 on the flats at 60 to 65 mph and fell to 11.5 once I hit the mountains. I was more impressed with how it took the hills. 5th gear on a long 6% grade and it stuck at 60. All the while passing big rigs struggling up at around 30. Felt pretty awesome. I know I am over weight but had to do it. Moved up here and only wanted to do one trip. CAT scale put the rig at 26k. The only mods I have are cts2 in tow, 4” turbo back exh., AD LP and deletes. I bought this truck new and did all the maintenance as scheduled and will have it for the rest of my days. Also agree a tail wind helps a lot and going over 65 kills the mpg avg.. cruise control also is not good for the mpg
 
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