Community Forums

cekkk · 07-04-2019, 03:09 PM

I just noticed this was a motorhome for him but since I am here. My 7.3 f350 Diesel gives me just under 11 miles per gallon at 62 miles an hour on long trips, meaning over 500 miles each direction.

I have gotten a bit more and a bit less with varying weather and road conditions but in general, I just think of it as 11 miles to the gallon.

Dutchstar411 · 07-04-2019, 03:11 PM

Do most of our driving on the Florida Turnpike and I rarely see any Motorhome do less then 65-70 MPH and they are usually towing something. Most of the time I'm at 70 to 74 MPH and always drive at that speed, varies because if most traffic is at 75 to 80 they'll pass me and I can stay on CC at my normal driving speed. I've got a 2002 40' Dutchstar pusher. With my AC's on using my generator I've always maintained 6.5 to 7 MPG. I do not tow anything and do all of our trips in Florida. Been doing this since I got the coach, third set of tires a couple years ago.

Texas John · 07-04-2019, 03:13 PM

We cruise about 60 mph in the right hand lane. I know many go faster. But our trip is about the journey as well as the destimation and we are comfortable at 60. We also limit our daily progress to about 250-300 miles or six hours max. Try to stop by 4:00 but no later than 5:00 to get camp set up!

Margaritaman · 07-04-2019, 03:21 PM

Hmm is this a joke I thought you had a 2002 Cummins 350 mileage was never that good on those and if you are a senior member you should know that. I did not read all your posts so if you upgraded you also should have known better then not to verify before you bought.

tjshively · 07-04-2019, 03:21 PM

Did you really think the previous owner just telling you the truth?
No one, absolutely no one tells the truth about their fuel mileage.
I run a Cummins 400HP at 65 and I get 8.0 to 9.0. Mostly 8.4 and that's the truth !!!

hex nut · 07-04-2019, 03:21 PM

I have a diesel pusher, gross weight 33,000 lbs., 400 horse power Cat with the Allison 6 speed automatic. The objective running down the interstate is to keep the transmission in the highest gear (avoiding unnecessary downshifts), and the diesel engine at the lowest rpm that will maintain that highest gear. On my coach, that sweet spot is 62 miles an hour. Above that, the rpm's go up and it sucks more fuel, below that it downshifts to 5th gear on the slightest rise in the road. Towing a 4000 lb. automobile behind it, it gets 7.5 to 8 mpg. I consider that excellent mileage for the weight I'm pushing. A smaller engine might have gotten better mileage, but then I would have been frustrated with it's lack of power. I like my Cat C-9 400 horsepower.

Stephens1509 · 07-04-2019, 03:21 PM

We have a 2018 Ford V-10 36’ gasser and average 6.5-7 typically running at 62-65.

EVMIII · 07-04-2019, 03:22 PM

I think every engine, including my Triton V10, has a favorite cruising speed. For me, pulling a Jeep 4dr, is 64-65. I think the guys with the big diesel pushers can cruise considerably faster without any strain. Rode with a friend to Talladega a couple years ago in a 45' DP and we never went less than 80mph and it felt smooth. Last year he did the same thing and I cruised along at 65 and he was 6 RV's in front of me in line to get on the track. I am fully on board with taking my time and enjoying the journey. Stay safe.

Mr. Re · 07-04-2019, 03:26 PM

My wife says I get 6,5-8.5 mph on flat Highways (Arizona-New mexico) depending if going 60 or 80..
My advice to new RV’ers is don’t ask questions about (1) fuel economy & (2) coach expense as answers are always disappointing & frustrating.
I remind my wife that we RV for (1) comfort (2) enjoyment (not economy or efficiency) and don’t bother about matters we don’t control.

Mr. Re
007 Scepter 38ft 400hp

r.davis · 07-04-2019, 03:26 PM

We have a 2015 palazzo 33.2 300hp Cummins 62 -63 mph 9.6 sometime 10.4

OlJB · 07-04-2019, 03:28 PM

I think 12 mpg was wishful thinking on his part. It amazes me how many people don't know how to calculate mpg, but are stating amazing figures. He was probably getting 8.2 mpg.
What is the speed rating on your tires? Go to https://www.discounttire.com › Tips & Guides to find out where the speed rating is listed. This is a starting point.
From what I have read, most people run at speeds of 65 to 68 mph. What is comfortable for you? What feels like a good towing speed? Our 2012 Ram 3500 DRW, towing a 37' Montana 5th wheel felt most comfortable at about 68 mph. The tires on re 5th wheel were rated at 81 mph, and the truck tires higher.
How old are your tires? If over 6 years old, you should probably replace them. For most RV's, tire age seems to be the determining factor, not tread depth.

firebird92 · 07-04-2019, 03:30 PM

I cruise at 64 mph and mostly use the cruise control. Average 8.8 mpg in a 2015 Winnebago Forza DP, 340 hp. Usually have wind due to being in Texas and seems like everywhere we go the wind is either quartering headwinds or headwinds. No wind we get 9 to 12 mph.

lrpendant · 07-04-2019, 03:31 PM

Have a 2011 Tiffin Allegro Breeze 28BR and the on board avg is 13.5 mpg. I try to maintain 62-65 in the right lane on the highway. Just added a ScanGauge to get a fresh start on the actual mileage.

Grandpa5x · 07-04-2019, 03:36 PM

I cruise at 62, that seems to be the sweet spot for my drive train, 8.1L V8 w/Allison transmission 38’ Mountain Aire. Do you drive strictly on cruise control? I gently use my foot to raise the power when approaching any kind of grade such as intersections or small hills to keep the cruise control from causing a downshift in the transmission. Best I can do is 10 mpg on FL flat ground, most of the time in normal terrain it’s round 8-8.2, the previous owner my have been a used car salesman in the past and you know their reputation for selling cars. Lol