42 k lbs loaded with toad 550 hp 1875 torque cat 3406e 7.5-7.9 mpg at 63 mph . but I bought the coach for the power to use cruise on most hills and not have to down shift . that is way more important then any mileage . my last coach was a dog on the hills .

get the biggest engine you can afford and enjoy the ride

We are getting 9.5-11.0 with a 2003 Fleetwood Excursion 38U cat 3126B towing 6x10 utility trailer around 1600. Lbs

Caveat: Unofficially via my Scan Gauge, which resets between shut downs, and primarily driving along the Eastern Seaboard with little mountain terrain:
60,000 miles via
2012 Tiffin Phaeton 380 Cummins on Freightliner towing Honda CRV @ 65 mph
Average 9.7 (seems higher than others - I will recalculate total trip distances now)

2004 Newmar Kountry Star, 3136 CAT 330 HP, 3000 series Allison 6 spd. Varies from 6.9 - 9.8 MPG depending upon speed, wind, terrain, and generator use. Sweet spot is 58 MPH no wind, no generator, mild terrain for 9.8 MPG. No toad.

FWIW, both my 2011 Phaeton and our 2013 Bus gauges read 20% plus higher than actual hand calculated.

05 Country Coach Cat C9 towing a GMC Terrain. 63 MPH 6 - 7MPG depending on terrain, as previous member said fuel mileage is what it is. , maintenance is where a lot of the $ comes into play. That being said, I certainly like my DP so much more then my previous gasser.

2000 National Tradewinds
 

Hi
300hp CAT
between 8 and 10 mpg traveling hwy at no faster than 62 or 63

Mpg
 

05’ Winnebago vectra 40’. Pulling a Subaru Forester. 7mpg average at 65-72 mph.

Diesel pusher MPG
 

1997 Monaco Dynasty 38’ 325 HP Cummins
Allison 6 spd auto. Pulling 98 Jeep Wrangler I like 60 mph 9-10 mpg consistently.

2008 Tiffin Phaeton 36', pulling 2014 Honda CRV. 8 - 9 mpg, Cummins 360 HP, often adding Stanadyne Performance fuel supplement. I cruise at 55-62 mph regularly.

Not exactly in your search parameters, but my experience:

My first DP, a 2003 Itasca Horizon, 32T (yes, 32 foot a shorty) with Cummins 300, over 3 years, averaged about 9.8 mpg. One tankful, under ideal conditions, we hit 11.5 mpg.

Our current DP, a 2010 40' Winne Journey 39n Express, Cummins 340, towing a Jeep Wrangler, on an around the country trip of 14000 miles, averaged 9.3 mpg. We usually drive between 58-64 mph. (no DEF in this model)

But up hills, or with lots of headwinds, the mpg drops considerably, but all part of the lifestyle. And another note, we do see noticeable improvement in power and mpg, with no or only B5 the lowest bio-diesel added.

DP mileage
 

I have a 39 foot Winnebago w a 330 CAT pulling a Suburban on an aluminum trailer. I run with the flow of traffic (averaging 70 mph) and I get between 7.5 - 8.5 MPG.

Just south of where you liveAttachment 232993

I've owned 6 DP 350 hp to 500 hp all have averaged 7 to 9 mpg. Currently 2014 Dutchstar 40 ft 450 hp 7-8 mpg towing a Jeep Wrangler 4 Dr.

2006 Monaco Cayman Cummins ISB 300 towing 2015 GMC Terrain. I get 8-9 MPG cruising at 63-64 MPH.

UK Driving
 

We have a Winnebago Vectra 40ft CAT C7 Allinson 6 speed auto

We average 12 MPG (imperial gallon) = 10 MPG US

In Europe we're limited to 60 mph, but as the trucks are limited to 56 mph, so most times we stick with the trucks (we're in no hurry!!)

We tow a tiny Citroen C1 and our winnie hardly notices it!!

As fuel is 3x the price in the US, I drive with a very gentle right foot and plan ahead!!

2016 Thor Tuscany 45AT forty five foot diesel pusher
 

In gentle rolling hills, around 8.2 mpg @ 65 mph (I-65 Chicago to Mobile)
In mostly flat terrain, around 8.7 mpg @ 65 mph (I80 Chicago to Cleveland).
In mountainous conditions, around 7.2 mpg @ 65 mph (I-84 Boise to Portland).
Forty five foot motorhome with tag axle, always pulling a 2015 Jeep Cherokee, always using cruise control, especially to resume speed from a standing start (much more efficient acceleration).

I don't have a DP but do pull a 5th wheel with a 2013 diesel. The DEP fluid is not much but with a load I would figure in the cost if mpg was something you worry about. Big truck fueling stations have a DEP pump or if you are cheap like me buy it at Walmart. 12-13 dollars for 2.5 gal.

DEP fluid is more of an agrivation than much of an expense. Falls under politics as some diesel engines are exempt.

'94 36' Monaco Dynasty, Cummins 8.3 ISC, Banks Turbo U/G, Allison MD upgraded to HD, typical GVW around 35000 lbs. 7 - 8 mpg, cruising on the interstate at 70 -80 mph using cruise control mostly. Note: Soft tire pressures give better ride but can reduce mpg by 1 or more. Set a little higher can save 1 mpg. Tire brands can have a big effect on mpg too. Goodyears -harsh -1, poor, Michelins - smooth - +.7, good, Dunlops - smooth - +.5, good, Bridgestone - okay - 0, average, Sumitomo - smooth - +.5, great(lasted 72,000 miles). I couldn't get them anymore so I'm now on the Dunlops(made by Sumitomo).

Average about 10. Cruise about 65, ever since tire shop mentioned any faster really heats up the tires. No mileage difference pulling our grand Cherokee. Mid to high 9 if really hilly.

Deisel Pusher MPG
 

Dan,
I did the following calculation in 2016 when we were making our final decision to purchase a 40 ft class A.

Estimate 10,000 miles per year on the bus
estimate 8 mpg
Calculated 1250 gallons of diesel

Worst case 1250 gallons at $4.00 per gallon equals $5,000 for the year
Reasonable average 1250 gallons at $3.00 per gallon equals $3,750 per year.

We decided that the cost of fuel was not a significant factor in our decision when deciding on what type of RV to own.

If you are paying $12-$13 at Walmart for 2.5 gals of DEF you getting screwed. DEF at pumps $2.50-3.00 per gallon. Its a known fact that onboard MPG computers are very optimistic. My mileage about 7.4 towing a Suburban. 62mph seems to be the sweet spot. I hand figure my MPG also. Nothing wrong with discussing this subject. If you don't think people with high dollar coaches should care, that's your opinion. Cummins ISB 9-10, ISC 8-9, ISL 7-8, ISX 6-7, Detroit Diesel 4-5. Anybody claiming a lot more than above is full of BS.

Tucson,
It's not that I don't care about fuel cost the point is that it's not a significant factor when deciding what RV to purchase. The fuel cost differential between one RV and another is the point. If you have a 35 ft travel trailer the tow vehicle will probably get a similar MPG as the class A diesel and once you park the RV you are still driving that tow vehicle to get around at some what better MPG but no ware close to the 20 MPG or better than what the folks in the class A get with their toad.

Point well taken, but the original OP was some one curious about DP MPG. Maybe those people claiming 12-13 were including their TOAD MPG.

2006 36' tropical 300 turbo Cummins deisal 36000 mi. I get 8-12 depending on wind. Just drove 8000 mi. On our last trip. Maintenence most important.

2006 36' 300 turbo Cummins, tropical mileage 8-12 , depends on wind. Last trip 8000 mi. I run it like I stole it. Good luck

March 2016 I bought my 2006 Discovery 39S with 26500 miles on the clock.
We do not have a tow and our top speed is 60-65 mph.
So far I made 5 trips with a total of 19.265 miles and burned 2395 gallons of diesel.
That is 8.05 mpg

I find it's best not to know, when we can we fill up and just take it easy keep to under 2000RPM.

Bazzer

Fleetwood Bounder 7.2liter.

Have a 43’ 2014 Itasca towing a 27’ trailer weighing about 11000 lbs and get about 6 MPG at 65 MPH

Diesel pusher MPG
 

2016 Newmar Ventana LE, 40 ft, 360 hp Cummins, 8.5 - 9 mpg

Cat 325, 37 ft 9 .1 mpg towing trailer, 9.3 towing truck. 150,000 miles.
 

9.3 towing. 37 ft Cat 325 , 2003 Safari 150,000 mi

MOG on 360 Cummins
 

Our in the city and on the road combination MPG is 7.7-8.0 MPG. Not sure what they are apart since my monitor does not calculate separately. Some say they get 8-10 MPG on the road. Still recommend a diesel pusher, quieter, plenty of power and more room to sit up front where you are driving imo

2015 grand tour , 450 isl cumins,towing 4dr jeep wrangler gets 5.5 to 8 mpg depending on terrain wind and speed

2014 Forest River Legacy 300 HP towing CRV. I don’t run wide open on most trips. Usually 61 or 2. I have gotten almost 12 and as low as 7. I think I get better than most bigger campers. It is what it is. If you stress out about the MPG, maybe it’s not for you.

2000 40’ Allegro bus Cummins ISC 8 to 8.5 consistently towing 4 door jeep wrangler

10.1 consistent mpg. 36' 1999 Fleetwood Bounder model 36s with Cummins 6 cylinder turbo diesel cruising at 60-65 mph. It's a year before your request range but thought you'd want to know.

2002 Monaco Windsor 40', 350 towing Ford Explorer Sport Track ... Average between 7 and 8, as a rule. We are in Oregon and have mountains on all sides.

Have not checked milage now that we tow a 2012 Lincoln MKX.

Driving a 2008 38.5 ft getting around 9 MPG when not towing the Jeep Wrangler. Towing I get around 7 MPG.

2001 monaco dynasty drywrought by driverside window
 

I have a monco dynasty with a 350 cumm we travel from fl to mn I pull a buick enclave and and adv. 9- 10 mpg speed 65mph

Almost consistently 5.5. 2007 Beaver Marquis. Cat 13, 45,000 lb.

2001 Monaco Dynasty 36’ 350 ISC with Tow Master dolly/2012 VW Jetta TDI

8.2 mpg at 68 mph mostly rolling hills but no mountains yet.

1997 Beaver Patriot 40' 330hp CAT pulling 4-door Wrangler. Last summer took a trip down to Disneyland, got 8.5mpg on the way down I-5/hwy99. Came up the coast on 101 and got 6.5mpg. Usually traveling with empty tanks with the exception of some water and usually travel between 55-65 depending on road conditions

2008 Damon Essence, 40 ft, 4 slides, 425 HP Cummings 6 spd Allison towing a 2013 4 Dr Jeep Wrangler Sahara. ave 8 MPG
Rig is for sale by the way.

Mileage
 

We have a 2006 Monaco Diplomat 40 PDQ with a 400 HP cumins ISL engine. Usually run around 65 on the interstate pulling a 2014 Honda CRV. We get around 8.0-8.2 depending on terrain. Our gross is around 34,500 pds.

We have a 2000 Foretravel u320 40' with a Cummins ISM 450 pulling a jeep wrangler. At 65 we get around 7mpg

Diesel mpg
 

Now that others told you what the mpg is. Can you afford it?
I have seen post where people ask about a fuel budget.
If you have to ask, maybe you cant afford it.
We have a 2007 bus. Bteak downs are more of a concern that mpg.
Had are bus for 2 years and extended warranty has pad close to $10,000 in repairs.
So, my personal opinion is that.
Good luck on what you decide!

just curious, what kind of '07 bus do you have??

Milesge
 

My 36 sportscoach has a 300 hp diesel. I get 11 MPG with my baby diesel.

Diesel pushed mpg
 

I drive a 2003 fleetwood excursion with a 330 cat avd about 7.5 to 8.5 driving 55 to 60 mph .ratfish

I think the question is certainly a valid one and one of interest to us as we find our current mini Class A a bit tight and were pondering a move to something a bit larger. Not everyone is rich enough to not care about the cost of traveling and most of us prefer making an informed decision whatever the topic.

For us, the less it costs to take a trip, the more likely we are to take it. I've owned a number of power boats over the years as well as a few hotrods and the cost of using them is always a consideration in how much or often.

This is our third motorhome and by far the most economical. It's an Itasca Reyo, 25' with two slides powered by a MB V6 turbo diesel and yesterday I averaged 14.5 at 65 towing a trailer with golf cart and it will get over 16 if not towing something. I joined a Yahoo group for these coaches before buying it and when I first read some of the members claiming 16-17 mpg, I wanted some of what they were smoking but now I'm a believer. Moving from this kind of mileage to something that gets half that wouldn't be done lightly.

Our first coach was a 34' Allegro, no slides, front engine Cummings and got 8-10mpg never towing anything. It wasn't great but at the time we only planned on RVing for 1-2 years max and the coach was a good deal used so we didn't concern ourselves too much about the mileage. Next we had a classic GMC, 26' with gas 406 Olds and it gets 10+ without towing anything. Ended up not using it much as the reliability of a 40 year vehicle isn't that great.

Now we'll take day trips all over the state without a second thought. I doubt I'd fire up a 38-42' coach as willingly.

2 different coachs, 2 totally different mpg
 

From 2004 through 2015 I had a 2000 Monaco Dynasty 40' w/Cummins 350 ISC towing a Cadillac Allante on a Demco tow dolly I drove 76,000 miles and consistently got 9+ mpg @ 65 miles per hour in every terrain in 48 states. In fact the lifetime engine mpg was 8.9 which included idle, maintenance and test drive times. It DID NOT have a tag axle.

From 2015 to the present I have a 2007 Monaco Dynasty 42.5' w Cummins 400 ISL towing the same car on the same dolly on many of the same roads at the same speeds and I feel Lucky if I break 6.5 mpg. It HAS a tag axle.

True, I have only driven this coach about 10,000 miles, but for mpg, it does not look good.

However, this coach rides better, handles better and stops better. I guess you have to decide what is more important for you. Do you get the most value or the most comfort.

Happy Motoring,
Art Perrone

Guess I'm not doing to bad
 

2006 Prevost conversion 51,000lbs+ with full fuel and water tanks towing a fully loaded Suburban from NY to FL through the hills of VA and PA at 65-70mph I average 6.1 for the whole trip.

I'm surprised more people don't get 10 mpg. I can average 10-10.5 mpg in Ohio and Indiana pulling a 26' trailer. BUT....put me Western Pa.,West Virginia, and some hilly areas I only get 8-8.5 mpg. I rarely go over 65 mph. Even my old Winnebago Vectra would average 9 mpg towing and 10-10.5 mpg with no trailer.

Cat C13 (525 HP) towing hybrid sedan just under 50,000 lbs combined usually 62-65 and average about 24 mpg on a trip. Sometimes a little more depending on how many local sight seeing side trips. This over last 50,000 miles ... Coach about 6, car 42 so averages to about 24 mpg. ;-)

2002 Travel Supreme 40' Class A - 8.8 400hp Cummins Allison 6 speed always driven in the economy mode cruise 60mph no toad (MC on a lift) get a steady 10 mpg. Approximately 36,000 lbs. Your mileage will vary depending on how you accelerate, what speeds you cruise at, how heavy is your towed vehicle, terrain (if you go up in elevation your mileage will drop, but you'll get it back when you come back down).
Peter

Well now, Miles per Gallon not important... knowing how to fix the rig Important. Watch out you don't put it on lease or finance contract and end up paying for a lifetime of interest.

Let the sun shine all through your holidays and if it rains I hope you got alot of space. Anything over 36 feet, you should have enough space...

Notwithstanding all the attacks on the validity of the question (you should not care about MPG and should not be asking this question) and all the "it depends on different variables, there is no answer, there are a lot so useful responses here.

Figuring out a ballpark budget, I can use 6.5 MPG, which helps both with budgeting and considering how much we might want to move around. this is helpful for addressing one of a hundred issues to consider. thank you to those who provided meaningful responses and to the OP for asking what is in fact a valid question.

Well said.

Quote:
Originally Posted by Jake21 View Post
6 years and over 100,000 miles full timing. Have no idea what my actual mpg is. I just fill when needed.


Well said.


Thats it. Hit the nail on the head.

:eek:Well, No. :nonono:

If you are using a gallon of antifreeze every 1,000 miles or a gallon of oil every 1,000 miles, this is something that is indicating a problem. :facepalm:

If you are getting 5.5 mpg on average and you weigh 35,000 lbs. and most others are getting 10 mpg, you might need to see if there is a problem. :blink:

That's the purpose of checking, to see if all the parameters are in order.

Going blind could bite you, and bite you hard! :eek:

Mark

2006 winnebago journey, 360 hp cat, 8.2 mpg pulling crv at 63 mph, 9 mpg w/o toad. .

2 weeks ago I was looking at a 07 Country Coach Intrigue with a Cat C13 on it. I had Cat dealer pull the ECM report. With lifetime 51000 miles, the average MPG was 6.

Oh By the way, if you have those cloud problems that'll affect your MPG.

Just saying... Going blind could bite you...

36’ Winnebago Forza 2014 with a 240 hp Cummins engine. We spend a lot of time on US and state highways and keep our speed at about 62 mph on Interstates. We consistently get between 10.5 and 12 miles per gallon.

6.9 0n Tropical 37.1' 350 turbo engine.

It's important to note that mileage can't be tracked accurately on a single tank. You have to check it over long distances and the course of time. On a large tank, you can't always get the tank to the same level depending on how flat the ground is at the refueling station. The lowest MPG that I have recorded on a single tank was 9.4 - with the highest at almost 13. Neither of those is a true representation of the actual fuel economy of the engine.

I think because of the differences in the amount of fuel I end up with in the tank at each fill up, I can't really see an accurate pattern with regard to fuel mileage for mountain driving vs flat lands cruising... though I am sure there must be a difference.

On a 7500 mile journey out west and back, our average MPG was 10.3 - but that includes the fuel used by the generator that ran 122 hours over the course of the trip. I put together a simple spreadsheet that allows me to estimate the amount of fuel that the generator uses, so I can come up with an estimate for the drive engine. I posted the results of our 7500 mile trip here: https://www.irv2.com/forums/f123/urge...ml#post3154432

FWIW... just remember that our pusher is light duty compared to what most people have. It's only 34' long, and right around 22k fully loaded... not to mention a more aerodynamic front end than most. It also has the old P-Pumped mechanical 12 valve Cummins - which has a reputation as one of the more efficient light duty diesels on the road.

cheers

Miles per gal?
 

In the industrial world of construction and open pit mining it is pretty much Cat or Cummings. Cats were harder on fuel and our shovels were more efficient with Cummings engines. In the RV world it seems to follow about the same. I think you will find it tough to beat a cummings engine. I had a Tiffin 37 Ap and at 12,000 miles was getting loosened up enough to get 12 MPG. We then had a 45 ft with a 6oo hp cummings and it got 4 and built up to 8 mpg depending on the wind. Wind is your best friend or your worst enemy. It takes time to break in a diesel and that is a good thing. Our presently new 2019 40 IP is getting 7 with 3,000 miles on it but I know that will increase as I get more miles on it. You may have to decide not to travel if it is a high head wind day or except a slower day traveling. Give it time to break in and use good fuel and good filters and good oil. Cheap will get you.:dance:

I get 8.2 mph over the 70,000 miles I have driven my coach. I have a 40 foot 32,000 pound coach with ISC 330 Cummings engine. I tow a 6000 pound Tahoe. At $4 per gallon it equates to about 50 cents per mile. I cruise between 62 and 70 mph.

I looked at your spreadsheet to see how you figured out generator usage if I'm not mistaken you chose half a gallon per hour and your generator size would be the 7.5 kW model I'm thinking, your usage was constant. I myself try to work out a number for my generator which is 7.5 kW and found the fuel usage depended on the percentage of workload on the generator I found it very difficult to come up with exact number's, it's just like guessing how many jellybeans in a jar. My rig also has 100 gallon tank with a diesel fuel gauge that reads in eighths, kind of nice as it's one big square tank makeing the diesel gauge quite accurate. So I watched fuel gauge and the load and the time over different week periods of Boondocking, it was all over the place, all because the loads very so much.

And You're right Piker, without thinking of this drainage from your fuel tank how can you accurately tell you're miles per gallon.

Just saying...

Correct... I settled on .5 gallons per hour for the spreadsheet that I posted, and yes that is an ESTIMATE. There is no way to know exactly what the usage is... however, the manual for the Onan DKD generator DOES state that at max load it uses .9 gallons per hour. The .3 gallons per hour minimum that I used was not from the manufacturer. That was a number I got off of another website and who knows if it's accurate.

The fridge, and two AC's are nowhere near taxing the capacity of the generator... so I used a number closer to the lower end of the spectrum than the higher. This would skew the mileage of the Cummins downward actually.

If you change the estimated hourly usage of the generator, it changes the mileage calculation for the Cummins:

.4gph generator = 11.1 Cummins
.5gph generator = 11.3 Cummins
.6gph generator = 11.5 Cummins

Worst case scenario, the generator is actually a perpetual motion machine that uses 0 gallons per hour over the 122 hours in the spreadsheet, and the Cummins ends up at 10.3 :cool: :D

The whole purpose of the spreadsheet was basically just because I like spreadsheets... and because I was curious... and because I wanted a baseline for budgeting trips. When we plan a trip, I estimate 10mpg overall, and we've never gone over budget on fuel. :thumb:

-cheers

Be sure to take these responses with a grain of salt, since this subject is one of the most lied about, along with those, who failed miserably at arithmetic.
We normally cruise at 57mph and for staying in 6th gear OD over hill and dale the average shown, on our digital readout over a period of 11 years, is 6.2 mpg, which I find to be pretty insignificant in the overall cost of ownership.
In fact MPG and RVing probably shouldn't be used in the same sentence....lol
Now, depreciation per mile is another story and find this well worth noting, if it's all about money and the newer it is, the worse it is. Having said that and with the age range you've stated, you'll be better off, than many.
The good news is, that you'll never be in need of another hobby....:dance:

Why do I always feel like I’m being called a liar when I post mpg of our rig? I mean, I’ve been called a liar before about it, but sometimes it doesn’t actually get said... it just gets implied? That’s a question... not an accusation.

Those of you with great big 20 and 25 ton rigs will definitely not see the same mpg as us. We basically have a glorified pickup truck chassis and engine... with an oversized Allison. Talk to the guys with the dodge trucks towing gross weights of 20k... they are all getting 10 to 12. Even the duramax and powerstroke guys get that. It’s not that unbelieveable.

All that said... yes, some people tell fish stories. And still others just don’t understand the issue of tracking mileage over time. If you look on my spreadsheet, one fillup showed 13mpg. The guy who doesn’t understand that his tank wasn’t really full at that station migh think he actually got 13. Like you said, it’s an arithmetic thing... but it’s not necessarily a lie.

One more point... checking fuel economy can be like checking the oil. Might tell a story if you have a problem somewhere. Exhaust appearance might not be as helpful. When we dusted our engine, we burned a quart every 250 miles... but when I looked in the mirror I couldn’t tell.

Ok... one final... final point. Depreciation is generally a big deal on these... unless you buy a hunk of garbage like we did and pay for the depreciation in repairs. And as far as fuel mileage... for those of us with old stuff, the fuel cost is actually a very large percentage of the cost of ownership. Ok... there was an extra point in there I didn’t warn you about. Send me a bill.

Cheers

Well your a great guy.
Keep cool.
You at least addmitted that you bought a pile of junk.
Blew the engine.
It takes a man to do that.
Regroup and move on , Enjoy.

You will learn there are things you dont discuss.[emoji23]🤣[emoji6]

98 Fleetwood American Eagle Cummins C8.3 w/ 3060 Trans, non waste gate turbo (32 psi) 325 hp - towing Jeep Wrangler 7- 8 mpg @ 65- 70 mph. Pushing a gross combined weight of 39,000 lbs. I could do better if I stayed between 60- 65 mph. Not retired yet so time is more of a factor.

Correction good sir... I never admitted to buying a pile of junk. I did admit to buying a hunk of garbage. Subtle nuance... :rolleyes:

Cheers

Piker's spreadsheet is GREAT!

I plan to fill up a full page on it this summer and then I be able to say what my mileage really is! Thanks to Piker's spreadsheet!

To the OP and as you can see, the numbers are all over the place.
Hard to believe that so many like coaches can be that far apart for fuel mileage, too.
I for one, will only rely of some sort of a computer for calculating my average and for over long periods of time.
We are the third owners of ours, which had an average of 6.1 when purchased.
In the last 2 1/2 years I've only been able to improve on this average, to 6.2, with my style of driving.
What I've never bothered to check, is if it's on the tank or the engine and if the genset, is being included, also. I'd venture to say it's the former and what the total fuel usage, actually is.
As a side note, the best way to save money on fuel, is for staying over at a Walmart on occasion. …………..and no, I'm not trying to start a Wally World War, here....:nonono:

I thought I might throw one more in, has you see, I use sledbiker, it's because I like snowmobiling and motorcycling they both weigh under 700 pounds they both have four cylinder four stroke engines on the snowmobile I get 11 to 14 miles per gallon and on the motorcycle it's better a lot better like three times better, I guess a lot of it is because of friction and drag. Anyway it's not because of the miles per gallon it's because of the Smiles / Miles... And that also lead me to believe that RVing would be the same and you know something it is...

The thought of burning a gallon of fuel, makes me think, about the same way as cooking a T-bone steak... And don't forget the beer...

Just saying...

We just returned from our madden trip and I was surprised that we got just over 10MPG! We were not towing and put a total of 335 miles on the coach. We just bought a Fleetwood Discovery 37T with a 330 HP Cat with 50,000 miles on her.


Robert and Jackie

You don't buy a diesel pusher if you are concerned with mpg. Just fill the tank and go and enjoy. Most will get right at 8.

Wow: I guess after reading most of these replies I now understand where the saying:


RESULTS MAY VARY AND PAST PERFORMANCE IS NOT AN INDICATION OF FUTURE RETURNS, LOL.



I bought a 2008 Fleetwood Bounder 38F with a 6.7 ISB Cummins 350hp engine and Allison 3000 trans. This power train won't necessarily give you whiplash when you step on it, even going down hill but the mileage has been decent. I have the DP and maybe I'm the modest income or net worth DP owner but mileage is important to me. Maybe I'm so pathetic that getting better mileage is the cheap thrill I enjoy at this ripe old age. Enough about me. I bought it with 29K miles on it in 2016 and have 40K and change on it now. I didn't get real fancy as Piker's spreadsheet which I'm really envious of but over the first 10,000 miles I used almost exactly 1,000 gallons. (I do keep a log). That included about 160 hours of generator time with my Cummins Onan 8000 genny. My mistake was I thought when I looked up the engine I read 1,700 rpm was peak torque. Last year my daughter the bought me my ScanGauge-D and I found out I'M BAD!!!! I looked up my engine again and found out 1,500 rpm is peak torque. While driving those first 10K miles I drove approx 61mph on my GPS which ran my engine around 1,720-1,775 rpm on the dash tach. Now I run 1,520-1,575 rpm which shows me around 55-57 on my GPS but has brought me between 11.6-12.5 mpg. I haven't make a long cross country trip since the change yet. The longest have been around 175mi legs. Hopefully, next month I'll take off for Yuma from here north of Green Bay and get a good idea of the trip performance. Maybe I'll be happy, maybe not. 8-9mpg isn't the end of the world but I enjoy getting better. I enjoy dry camping on my trip as much as possible while traveling. I guess, I'm sorta cheap, LOL.
Steve


[moderator edit]

Good for you, nothing wrong with being anal about wanting to know fuel mileage, or any other portions of motorhome services. Since we tend to go and want to get from A to B on whatever fuel the motorhome takes..so be it, but I'm one to travel at 60 mph pretty well all the time, as I don't believe we should be in a huge hurry now that retirement has arrived, as well as it's overall being safer to drive slower generally. Thanks for letting us know of your setup, and let us know when you find if your better mileage stays similarly if/when driving mountain regions as well. Always nice to know if most DP's are getting similar mileage, as I have the 360 HP Cummins in mine. Hard to believe my diesel pickup is set up win well over that HP in a much lighter vehicle, but the way the torque is set up with the Allison 3000 it seems to do just fine on hills even with towing.

Thanks Powerstroke2000
Your name caught my attention immediately. Prior to buying my DP I drove a 1995 Triple-E 29ft Class C. It was sort of a family MH. On a 3000 mile trip to Boston & back driving 57mph (no tach in it) I averaged 14.8 mpg. That old 7.3 Cornbinder PowerStroke was such a smooth running engine. After buying my DP I sold the Triple-E to a friend any he's consistantly averaging 14.5-15+ mpg. If that MH had at least 1 slide I think I'd have bought my brothers out and kept it. What a far cry from the 6.0 PS that ford replaced it with. I hear the newer 6.7's are back to being good engines. I'm not experienced with the DEF engines yet. I drive a 2018 Chev Colorado with a 2.8 Duramax and a 2019 Equinox 1.6 liter diesel (toad vehicle) but they only have 4,000 and 2,900 miles on them respectively so I haven't had to add DEF yet. They're small but I like the mileage. The Colorado gets mid 30's at 70mph and the Equinox is in the 40.'s. I've heard that the DEF engines in pickups aren't a economical as the pre-DEF. But, I'm not in a position to make a valid judgement myself.


Steve


[moderator edit]

I'm currently running an '09 F450 with the 6.4 which has in excess of 500 HP, albeit I never run it hard, but without the emission need for DEF and a Programmer it has a ton of power, where before buying the DP motorhome I had an Arctic Fox camper in the bed, then an 18' enclosed trailer with 'toys' behind. There really where not many hills I couldn't do the speed limit on, as I did watch my EGT's (exhaust gas temps) and kept them in a safe temp when pulling hard. LOVE the truck, as it's SO comfortable, is 4X4 and has been a great truck over the years, but will be selling it in the coming months. I never did check the mileage on it, as I just fill the tank as needed, and even would add a diesel fuel supplement from time to time, so that of course is added cost, but I hoped it was doing some good to the fuel system, never a bad thing. I do find getting a full service on the Cummins annually is quite a hit to the pocketbook, but keeping it in top shape is important I believe. I'd like to start doing my own oil changes and fuel filter changes, which may save a little. I try to do as many of the smaller jobs as possible on my rig, and as I learn more I may do more in the future. Be safe, be free! :)

Mr. Steve, regarding your Bounder, is your 3,000 transmission a 5 speed?

We have the 4,000 six speed Allison and at 55 mph I'm turning 1,200 RPM's in 6th gear. The Allison will shift into 6th exactly at 55 mph. We can stay in 6th gear down to 50 unless I really push the throttle.

Just curious.
Mark

You don’t buy any RV if you are worried about MPG.

Have a 35 footer. Get 12 to 14 mpg. Get much better setting in campground.

Depends on how you define “worry” though doesn’t it? I’m not necessarily “worried” about mileage, but when I was shopping for a used motorhome (aka “hunk of garbage”) I decided that the old 12v Cummins/Allison 3060 combo would be the best fit for us... for several reasons... one of those being fuel economy. Why spend more money on fuel if you don’t have to? For us, it means 20% more traveling over something that gets, well... 20% worse fuel economy. :rolleyes:

Those of us who are motorheads love the hp and torque of these rigs. Calculating fuel economy... finding the sweet spot for the best mileage... and tweaking performance is all part of the hobby. For others, the whole thing is mostly a lifestyle choice, and the mechanical stuff isn’t part of the hobby. To each his own, right? Unless you’re involved with a forum and then you type with one hand and fling poo with the other. :D

The modern V8 diesels in the pickup trucks are awesome. They have the low end grunt you associate with a Diesel engine, but run at high enough Rpms to produce ridiculous horsepower. Makes for a lot of fun. We had a 2002 4 door dually duramax with a 4” turbo back exhaust... PPE tuner... and a 56 gallon custom fuel tank. It was like driving an 8000lb sports car. 450 hp... 18mpg on the highway empty... 15 around town... and around 11 loaded up at 23,000 lbs with a trailer. It was a serious hoot! You know... if your into that kind of thing. :whistling:

The smile on my face when I’m driving my still new to me DP tells me I’m not to concerned about mpgs lol. If I were to guess, it’s about 8. Leaving Sunday, will do a real math check and get back.

MPG- Really depends on the terrain. We usually put in around $70 - $100 per a trip and don't go more than 280 miles in a trip.

Year: 2009
Model: Tiffin Allegro Bay
Length: 37 Ft
Cummins 375
interstate cruising speed driven: 60ish

Well said, there's a lot of BS! It's just a simple question, answer it in a simple way. How much did your fishing line cost, WELL if you got to asked how much fishing line cost, you can't afford to go fishing..

I see or saw that some are talking about RPMs to get better MPG's. I know my coach when climbing long big hills and if you lugg the motor to a point were it is forced to gear down, take a look down at the temp gauge. Now if you had forced the gear change earlier by throttle control the higher revs will cool your motor down, of course's this is for all the older models with out electric fan controls or hydraulic controled fan side radiators.

So I guess my point is, how much more diesel did I burn wasn't so important, I'm happy she's happy and she runs like a Cat not a Dawg.

This was 15 years ago when I was on the diesel forums with my 6.0 ford. When mpg was discussed it wasn’t about rpms, it was about exhaust temps. The closer to 600 you could keep it, the better your fuel mileage. BUT, that was on a deleted truck before all this emissions crap.

I know Jimmie made a V 12
I wasn’t aware of a Cummins V 12 diesel

Is it even possible for researching and finding the best quality coach possible for yourself and one that meets your budget, if you're also trying to narrow it down to the best fuel mileage, as well?
With our last purchase, I gave no consideration whatsoever to it's would be fuel economy vs other units, which would have most surely, driven me crazy, as a result. I mean, now much difference can there actually be and would find that one's style of driving would be more important.
As a last resort, like I've always said for putting free fuel in your tank, stay at a Walmart or other, overnight.....:popcorn:

Well said...:thumb:

Bingo! mine (1998 36' Windsor, 300hp cummins) gets about 8 towing a jeep.

8-9 MPG @ 62-65 MPH, have 2011 Berkshire 38' DP with toad 340 HP

Newmar 43' Ventana with 8.9 ISL and 3000 Allison transmission. Weight is 42,000 lbs give or take a little, flat towing a Honda CRV.


8.2-8.9 MPG HIGHWAY
Right around 7 MPG in traffic. -Paul

We have similar coach. 2001 Newmar Dutch Star 3851, same engine and chassis as you, we tow a LOADED GMC Canyon, full water, stuff in bays, we've gotten as low as 6.2 mpg, as high as 8.4 mph measured by miles driven and fuel put in, NOT an electronic measure devise that may or may not be "weighted" to make people feel better about their rigs!

If running a generator, it adds .332 gallons/hour to fuel consumption (figured over a 98 hour continuous run, using AC etc) RV was filled w/ diesel, driven about 5 miles to location, ran 98 hours, drove back to same gas station, same pump (same slant to the pump parking area), filled up full, deducted 10.6 miles at 7.4mpg for drive. I figure 1/3 gallons/hr is pretty accurate, but I still use 1/2 gallon/hr for planning purposes.

We drive from 62 to 70 mph on the interstate.

I get a kick out of those people who are driving 40+ foot Class A's and are claiming to get over 10mpg!:D