Realilistic mileage with a fifthwheel.

[grizz272]

Just curious what kind of fuel mileage I can expect with a fifth-wheel.
1ton 4x4 duramax srw 36 Ft. 13Klbs fifth-wheel. I realize weather, road conditions whether it is flat or hills or mountains all can make a big difference. Generally speaking flat lands like the whole god forsaken state of Illinois.

[Cummins12V98]

justme wrote:

Cummins12V98 wrote:

justme wrote:
Last summer I got 12.1mpg average from San Francisco to Connecticut on my 2012 F350 diesel pulling a 40ft trailer. I set my cruise control to 62mph most of the time. I got 12.2 mpg from Connecticut to Florida recently. I use ctane additive/booster all the time and never use B20.....

Using display or hand calc? What is your combined weight and is your RV a wide body? Most people never use B20 since the tag says "up to B20".

I'm using the display after I determined that it is accurate and my combined wieght is 24260 according to the CAT scale. Also it is not a wide body. Ford says B20 is OK and does not say up to B20. However they recommend ether 5-40 synthetic or 15-40 non synthetic with B20 which is the same recommendation for severe duty. B20 burns hotter and does not have the BTU content that diesel #2 has which means translates to lower efficiency and less MPG. Also B20 is harder on the high pressure fuel pumps and injectors on the newer trucks.

These signs at the pumps typically say "up to". I actually get my BEST mileage running this along hwy 99 between Bakersfield and Sacramento, CA.

[fallonator22]

We recently did 8.5 to Orlando from Houston, 9.5 on the way back. 2015 2500hd duramax denali pulling a 40'6" sandpiper, ~14k lbs.

[justme]

Cummins12V98 wrote:

justme wrote:
Last summer I got 12.1mpg average from San Francisco to Connecticut on my 2012 F350 diesel pulling a 40ft trailer. I set my cruise control to 62mph most of the time. I got 12.2 mpg from Connecticut to Florida recently. I use ctane additive/booster all the time and never use B20.....

Using display or hand calc? What is your combined weight and is your RV a wide body? Most people never use B20 since the tag says "up to B20".

I'm using the display after I determined that it is accurate and my combined wieght is 24260 according to the CAT scale. Also it is not a wide body. Ford says B20 is OK and does not say up to B20. However they recommend ether 5-40 synthetic or 15-40 non synthetic with B20 which is the same recommendation for severe duty. B20 burns hotter and does not have the BTU content that diesel #2 has which means translates to lower efficiency and less MPG. Also B20 is harder on the high pressure fuel pumps and injectors on the newer trucks.

[laknox]

I ran B99 off and on for several years in my '02 D'max. Truck ran much quieter, got better mileage and smelled like french fries instead of smoke. :B Even "fixed" my fuel gauge sending unit when it went wonky on me.

Lyle

[Cummins12V98]

justme wrote:
Last summer I got 12.1mpg average from San Francisco to Connecticut on my 2012 F350 diesel pulling a 40ft trailer. I set my cruise control to 62mph most of the time. I got 12.2 mpg from Connecticut to Florida recently. I use ctane additive/booster all the time and never use B20.....

Using display or hand calc? What is your combined weight and is your RV a wide body? Most people never use B20 since the tag says "up to B20".

[justme]

Last summer I got 12.1mpg average from San Francisco to Connecticut on my 2012 F350 diesel pulling a 40ft trailer. I set my cruise control to 62mph most of the time. I got 12.2 mpg from Connecticut to Florida recently. I use ctane additive/booster all the time and never use B20.....

[Johnny_G1]

Type the number of Liters per km (l/km) you want to convert in the text box, to see the results in the table.

16.3 l/100km is equal to 0.16 l/km
Metric
Liters per km (l/km)
0.16

Liters per 10 km (l/10 km)
1.63

Liters per 100 km (l/100km)
16.3

Kilometer per liter (km/l)
6.13



U.S.
Miles per gallon (mpg)
14.43

Gallons per 100 miles
6.93



British
Miles per gallon (mpg)
17.33

Miles per litre (mpl)
3.81

Gallons per 100 miles
5.77

A conversion table I found.

[Johnny_G1]

fj12ryder wrote:

Johnny G1 wrote:
A recent trip to the Arctic Circle this past summer, 28' Travelaire loaded and I average 16L per 100K 8000K or 5000 miles mind you the dodge is pumped up a bit so 17 mpg was easy to take.

17 mpg might be easy to take, but 16L per 100K equals 14.7 mpg. Still a bit high, but more believable than 17 mpg. 🙂

Been doing some recent figure's on fuel I used this summer, computer showed 16.3L per 100k and since we live in Canada
and our gallon is 4.54L, the fuel used in my dodge figure's out to 17.3 MPG which is what I thought it should be, and all liter's used are on receipt's for the miles travelled. Also every mile was clocked on a garmin gps for hour's travelled and time stopped. Just my thought's

[CabinetmakerII]

This year from Idaho to Arizona, first 2 days 6-7mpg due to headwinds... final leg from Havasu to Yuma 9-10mpg. Best I have ever gotten is 12mpg but I had a tailwind and flat towing Eastbound on I-84 through the Columbia Gorge

[Cummins12V98]

I love the pumped up stories! I have heard a few doozies while traveling at the pumps.

[fj12ryder]

Johnny G1 wrote:
A recent trip to the Arctic Circle this past summer, 28' Travelaire loaded and I average 16L per 100K 8000K or 5000 miles mind you the dodge is pumped up a bit so 17 mpg was easy to take.

17 mpg might be easy to take, but 16L per 100K equals 14.7 mpg. Still a bit high, but more believable than 17 mpg. 🙂

[Johnny_G1]

A recent trip to the Arctic Circle this past summer, 28' Travelaire loaded and I average 16L per 100K 8000K or 5000 miles mind you the dodge is pumped up a bit so 17 mpg was easy to take.

[StirCrazy]

43tutor wrote:
For what it is worth, my truck (1996 F250, 7.3L diesel, 4.10 rearend, manual transmission) was getting around 10 mpg towing. This spring I made a few upgrades. All new 4" exhaust, eliminated exhaust particle filter on exhaust, removed exhaust back pressure valve, added a TS performance 6 position chip, and rebuilt the turbo (stock configuration). Now the truck consistently gets 12 to 12.3 mpg towing at 65 mph (11,000 lb 5'er) with the chip set on 50+ HP. Daily driving to work (250 miles per week) the truck went from 18 mpg up to 22.5 mpg (mostly interstate driving at 65 mph). I've tested different positions on tuner chip and it seems like 50+ HP is the sweet spot best mpg. I can dial up to 140+ HP with this chip for hill climbs if needed but so far 50+ is enough. Exhaust gas temperatures with the chip set at 50+ HP keeps the 7.3L in the safe zone.

ok so I want imaging things, I did one trip with my old 99 7.3 which was modified and got 15.7mpg cdn which is 13.1 US in the mountains, and I have been trying to get there with my new truck but I don't think I will in stock form, so until the warranty runs out...

Steve

[43tutor]

For what it is worth, my truck (1996 F250, 7.3L diesel, 4.10 rearend, manual transmission) was getting around 10 mpg towing. This spring I made a few upgrades. All new 4" exhaust, eliminated exhaust particle filter on exhaust, removed exhaust back pressure valve, added a TS performance 6 position chip, and rebuilt the turbo (stock configuration). Now the truck consistently gets 12 to 12.3 mpg towing at 65 mph (11,000 lb 5'er) with the chip set on 50+ HP. Daily driving to work (250 miles per week) the truck went from 18 mpg up to 22.5 mpg (mostly interstate driving at 65 mph). I've tested different positions on tuner chip and it seems like 50+ HP is the sweet spot best mpg. I can dial up to 140+ HP with this chip for hill climbs if needed but so far 50+ is enough. Exhaust gas temperatures with the chip set at 50+ HP keeps the 7.3L in the safe zone.

[StirCrazy]

Cummins12V98 wrote:

racer4 wrote:
10.5-12 mpg at 62 mph with 20,000 miles on the odometer.

I question this also!

you question it and I am sitting here wondering what the rest of you are doing to get such lousy mileage haha.

I tow a 37.somthing cougar fifth with a 2014 f350 diesel (4x4 SRW)

I normally drive between 55-65 mph

I live in the middle of the mountains and I get between 20L/100km (11.8 mpg US) and 19 L/100km (12.4 mpg US) I did get 22 L/100km (10.7) on the way home last summer but I had a brake that fell apart and was dragging.

in the flat lands I get between 19 L/100km (12.4 mpg US) and 17 L/100km (13.8 mpg US) and I think if I slowed down to 55 mph for the whole trip, I could squeeze a bit more.

Steve