I just can't believe so many people have lied to me...

John From Detroit said:

One thign to consdier, as I said, 38 foot motor home 9-11 MPG with a fresh wax job not towing, 8.1L on paper is not much different than the ford V-10.  Should preform about the same.

Towing 7-9 but I have not been able to wax it.. May get that done soon. (Health and weather issues).

I think 22 MPG for a 22 foot C is not out of line BUT, you got to try it to be sure, and it will depend on how you drive, and of course I'm giving best millage in the above, not overall average.. But here is a consideration.


I know folks who have a honking big pick up and a 35-40 foot 5ER... Towing ,,, they get the exact same millage I get.

Bobtail (Pick up only, not trailer) they get..... about half the millage my car gets and it's an older car, today's cars get half again what my current towed gets.

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I don't drive a car, so even if I had a motorhome I'd still be pulling around a full size P/U. Might as well pull a trailer with the P/U.

BoomerD said:

Gawd...I WISH...I'm in Washington State. Gas here is almost $4/gallon again. To my great surprise, it's 30-40 cents/gallon cheaper in Norcal where we used to live. (it used to be the other way)

Anyway...some folks seem to be missing my point here. It's not that I'm surprised to find out motorhomes get crappy gas mileage...I expected that...I was making light of all the sellers (dealers and private parties) who felt the need to lie about what great gas mileage their coaches will get.

Maybe I should hunt around for the "miracle" gas mileage gadgets that pop up from time to time...I'm SURE they work as advertised... (I KNOW it's true...I saw it on the intarweb!)  ;D

http://www.popularmechanics.com/cars/alternative-fuel/gas-mileage/1802932

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When I was attending GMI (General Motors Institute) in the 70's, I wrote a paper about all of the gadgets that claimed to increase you mileage by 10-20%.... there were multi-electrode spark plugs, carb base plates with little fans in them, special air filters, fuel additives, special fuel filters, oil additives,..... etc, etc. I added up the combined value of each product and came up with an engine that could produce copious amounts of gasoline.....  :

On a serious note, putting in taller gears in the differential could very well have the opposite effect unless you only drive on flat-lands and never when the wind blows against you. Also, it would be quite cost prohibitive and even more than that, there are very few technicians that can set up ring & pinions properly and your chances of an early failure would actually increase. Having said that, you can install a GearVendors  (or similar) overdrive unit on the back of your transmission. That would give you the advantage of running your current gear ratio while on hills or bucking a head wind or allowing an over-drive to kick-in while on the flats and/or tail-wind. This would definitely increase your MPG.

Wavery said:

When I was attending GMI (General Motors Institute) in the 70's, I wrote a paper about all of the gadgets that claimed to increase you mileage by 10-20%.... there were multi-electrode spark plugs, carb base plates with little fans in them, special air filters, fuel additives, special fuel filters, oil additives,..... etc, etc. I added up the combined value of each product and came up with an engine that could produce copious amounts of gasoline.....  :

On a serious note, putting in taller gears in the differential could very well have the opposite effect unless you only drive on flat-lands and never when the wind blows against you. Also, it would be quite cost prohibitive and even more than that, there are very few technicians that can set up ring & pinions properly and your chances of an early failure would actually increase. Having said that, you can install a GearVendors  (or similar) overdrive unit on the back of your transmission. That would give you the advantage of running your current gear ratio while on hills or bucking a head wind or allowing an over-drive to kick-in while on the flats and/or tail-wind. This would definitely increase your MPG.

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Yeah, I've been around long enough to know those products are all "snake oil." Perhaps my "change the gears" comment didn't come across as tongue-in-cheek enough...it was meant as highly sarcastic. (and I know sarcasm doesn't always show well on the intarwebs)

Well...we took "Minnie" out for her maiden voyage this past week. Drove about 300 miles...averaged about 9.25 MPG running the cab air conditioning for much of the drive. Plenty of "elevation changes" as we went up and over Mt. Rainier via hwy 410 then south to US 12 to the lake.
Handled nicely, (except for one "woo-hoo moment" when I hit a rough patch of road and the coach seemed to want to go a different way (toward the cliff) than I was trying to go...   )

We have decided the coach is just too darned small for us and the grandchildren (ages 10, 12, 14) but should be just fine for the two of us.

Right now the big problem with propane is as stated not good availability and cost. You will also find there is less energy in propane so you will get less mileage. Cheeked on price of propane today in Fresno Ca. 4.00 gal.
Bill

WILDEBILL308 said:

Right now the big problem with propane is as stated not good availability and cost. You will also find there is less energy in propane so you will get less mileage. Cheeked on price of propane today in Fresno Ca. 4.00 gal.
Bill

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Propane here (Silverdale, WA) is $3.99/gallon...thankfully, it's only for water heating, cooking and refrigeration while on the road, this time of year.

How's Frezburg? I have a few friends down there.

Wow!!! I just paid $2.35 for propane (for our house) yesterday.

The big issue with propane in piston driven engines is that it has no lubrication qualities. In fact, with each intake stroke, the propane "washes" the cylinder walls. Propane engines usually wear out piston rings somewhat sooner that gas engines.

Wavery said:

Wow!!! I just paid $2.35 for propane (for our house) yesterday.

The big issue with propane in piston driven engines is that it has no lubrication qualities. In fact, with each intake stroke, the propane "washes" the cylinder walls. Propane engines usually wear out piston rings somewhat sooner that gas engines.

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sorry your wrong.I installed LPG systems on vehicles for years and also rebuilt engines and never ever saw where the rings on a LPG wore out  "somewhat sooner"
They were much harder to get a good ring seat upon break in  on new engines .In fact because LPG burns virtually carbonless  LPG engines lasted way way longer and 4 times the miles on a oil change.Valve,s  and Valve seats were a problem though due to high valve temp caused by LPG.We use to install special hard seats and valve in LPG engines on rebuilds
LPG for home heating is most likely cheaper because of no road taxes etc. I paid $3.65 per US gallon last winter for BBQ bottle fills

I've got to disagree on this one. LP engines actually last much longer. One reason is they are cleaner burning with less hydrocarbons and secondly they gasoline fuels wash the lubricants off cylinder walls but LP is in a completely gaseous state when it enters the combustion chamber. One of my old work trucks mad over 250,000 miles, everything was worn out on that truck except the engine. I have two lincoln welders here now that run as well as they did their first day and they are at least 30 yrs old and used on commercial work for pipefitters.

I hate to disagree with you on this one Waverly because you are mostly right on other things but I had to this time.

Well..... I must admit that my experience with LP vehicles is a bit dated. Back in the late 70's/early 80's the City of Los Angeles decided to switch all of their maintenance vehicles (mostly 3/4T pickups) over to LP. They purchased hundreds of them and we were their servicing dealer for warranty work. They purchased the vehicles new and contracted a separate company to  install the LP (it was not an option from GM). At about 35K miles, engines started burning oil and the City thought that GM should pay for the repair under warranty. After much research and testing, GM decided that the piston rings, valve guides and valves were wearing prematurely due to the use of LP fuel.

At that time, gasoline had upper cylinder lubrication additives in the fuel. LP did not. Admittedly, a lot has changed since the late 70's. The rings, valve train and heads are designed to last longer without the use of the same upper cylinder lubrication (lead). However, there are still additives in gasoline and certainly diesel that LP just doesn't have to this day.

Wavery said:

Well..... I must admit that my experience with LP vehicles is a bit dated. Back in the late 70's/early 80's the City of Los Angeles decided to switch all of their maintenance vehicles (mostly 3/4T pickups) over to LP. They purchased hundreds of them and we were their servicing dealer for warranty work. They purchased the vehicles new and contracted a separate company to  install the LP (it was not an option from GM). At about 35K miles, engines started burning oil and the City thought that GM should pay for the repair under warranty. After much research and testing, GM decided that the piston rings, valve guides and valves were wearing prematurely due to the use of LP fuel.

At that time, gasoline had upper cylinder lubrication additives in the fuel. LP did not. Admittedly, a lot has changed since the late 70's. The rings, valve train and heads are designed to last longer without the use of the same upper cylinder lubrication (lead). However, there are still additives in gasoline and certainly diesel that LP just doesn't have to this day.

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the GM 350 engines in late 70, to early 80,s were junk.The valve train definitely was the failing point with LPG but  usually much further down the road than just 35K.I have seen my share of failed guides in chev 305 and 350 engines of the era and while on gas. Rings I never saw as a problem due to LPG.Ring seat after rebuild was a sticking point when run on lpg I use to insiste  they be run in on gas for warrenty if at all possible
I did this for a living for 40 years.owned a LPG convertion center and a engine rebuilding shop

buchanan said:

the GM 350 engines in late 70, to early 80,s were junk.The valve train definitely was the failing point with LPG but  usually much further down the road than just 35K.I have seen my share of failed guides in chev 305 and 350 engines of the era and while on gas. Rings I never saw as a problem due to LPG.Ring seat after rebuild was a sticking point when run on lpg I use to insiste  they be run in on gas for warrenty if at all possible
I did this for a living for 40 years.owned a LPG convertion center and a engine rebuilding shop

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I was a GM Service Manager for one of the largest dealerships in CA. The City of Los Angeles converted over 500 vehicles to LP, lost millions of $ on the effort and have never gone back to LP again (to my very dated knowledge). GM pulled the engines from 35 of their trucks, ran extensive testing and proved to the LA gurus that the engines failed prematurely due to the use of LP.

As for you insult (as usual) toward the small block Chevy engines....... Those were the days of carburetors and big heavy engines. I saw more small block Chevy's cross the 200K mark than any engine that I knew back in those days. The reason that GM abandoned the 350 was due to weight and the superior design of the new generation (higher RPM) V8....... notice...... still no LPG offered.

NOW...... having said all that, that was back in the day of carburetors and leaded gas. I have not a clue what has changed other than the fact that none of the auto manufacturers offer LPG as an option to this day. GM (and other manufacturers) spent millions on testing LPG as a fuel platform and still does. Chrysler lost millions when they offered LPG. Every once in awhile, a foreign manufacturers (Volvo, and I think VW) will offer LPG but without exception, they have all (to my knowledge) dropped it after just a few years.

Then again....... maybe the guys that install LPG as an aftermarket device are all smarter that all of the auto manufacturers in the world.

Wavery said:

I was a GM Service Manager for one of the largest dealerships in CA. The City of Los Angeles converted over 500 vehicles to LP, lost millions of $ on the effort and have never gone back to LP again (to my very dated knowledge). GM pulled the engines from 35 of their trucks, ran extensive testing and proved to the LA gurus that the engines failed prematurely due to the use of LP.

As for you insult (as usual) toward the small block Chevy engines....... Those were the days of carburetors and big heavy engines. I saw more small block Chevy's cross the 200K mark than any engine that I knew back in those days. The reason that GM abandoned the 350 was due to weight and the superior design of the new generation (higher RPM) V8....... notice...... still no LPG offered.

NOW...... having said all that, that was back in the day of carburetors and leaded gas. I have not a clue what has changed other than the fact that none of the auto manufacturers offer LPG as an option to this day. GM (and other manufacturers) spent millions on testing LPG as a fuel platform and still does. Chrysler lost millions when they offered LPG. Every once in awhile, a foreign manufacturers (Volvo, and I think VW) will offer LPG but without exception, they have all (to my knowledge) dropped it after just a few years.

Then again....... maybe the guys that install LPG as an aftermarket device are all smarter that all of the auto manufacturers in the world.

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The  Low compression carburated 350CID GM built from around 1970 through 1974 were ok.Then from around 1975 through  1986  ish  they were not that great.But Stock They were never a great engine.Then The slightly changed TBI was a better 350 but still not great and the  last series the Vortec were pretty darn good.But as far as big and heavy I never saw a Big and heavy small block GM engine.The 350 was such a garbage engine in the late seventys early 80 GM was sued by Oldsmobile and Buick  purchasers because GM snuck in the chev engine in place of the olds or the buick 350 engines which were far superior to the junk chev 350
LPG convertions have diminished for several reason,s the main two Iam aware of is LPG has gotten too exspensive and the cost of convertions due to the computer controlled vehicles is just too exspensive to  justify any savings.plus the fuel distribution centers are few and far  between citys and towns
I personally never saw a engine "FAIL" because of LPG. I never saw a engine that was running good on gas and converted to LPG where rings then failed because of LPG.Just does not happen and MOST certainly  just Plain Engine FAILED Did not ever happen
I saw lots of valve guide,valve surfaces and valve seats slowly fail due to LPG gas but usually over long periods of time same as dodge and ford also
A lot of valve seat failures because of soft seats and  LPG set way richer than factory authorized settings
Also to note  I never actually saw nor heard of GM offering LPG as a factory option? what years and where was this offered  and would like to know how LA lost "MILLION,S" on 500 LPG convertions? I did around a 1200 convertions out of our little shop and never saw  A single Motor  "FAILURE" due to LPG
The main problem I encountered was getting rings to seat on new engines.I really preferred to break them in on gas before converting or use a Duel fuel convertion which were quit popular.  But am curious to know how LA lost "MILLIONS"  HOW?  WHY? 
By the way I never knew a human could actually "insult" a solid piece of metal.now that's funny. I did through my Automotive carrear meet a lot of service managers  in my many dealings with ford,GM,Dodge etc and 99% knew nothing about mechanics

Sorry to be so late to this discussion.  New to this forum. 

I think about fuel efficiency in a different way.

The math is simple:

A Prius weighs around 3,200 pounds and gets 45 MPG.  Multiply the 45 by 3,200 and you get 14,400 pmpg (pound miles per gallon).

My motor home weighs around 25,000, and the toad adds 3,400, i.e 28,400 total and gets about 7MPG (on a good day, with toad).  28,400 X 7 = 198,800 pmpg.

That makes it 13.8 times more efficient at moving pounds down the road than the Prius.  Not bad for something with the aerodynamics of a huge brick.  And excellent for a house!

Presented 'tongue in cheek' but this does illustrate the reason OTR trucks are still economical.

8Muddypaws said:

Sorry to be so late to this discussion.  New to this forum. 

I think about fuel efficiency in a different way.

The math is simple:

A Prius weighs around 3,200 pounds and gets 45 MPG.  Multiply the 45 by 3,200 and you get 14,400 pmpg (pound miles per gallon).

My motor home weighs around 25,000, and the toad adds 3,400, i.e 28,400 total and gets about 7MPG (on a good day, with toad).  28,400 X 7 = 198,800 pmpg.

That makes it 13.8 times more efficient at moving pounds down the road than the Prius.  Not bad for something with the aerodynamics of a huge brick.  And excellent for a house!

Presented 'tongue in cheek' but this does illustrate the reason OTR trucks are still economical.

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Your math is all wrong.

8Muddypaws said:

Sorry to be so late to this discussion.  New to this forum. 

I think about fuel efficiency in a different way.

The math is simple:

A Prius weighs around 3,200 pounds and gets 45 MPG.  Multiply the 45 by 3,200 and you get 14,400 pmpg (pound miles per gallon).

My motor home weighs around 25,000, and the toad adds 3,400, i.e 28,400 total and gets about 7MPG (on a good day, with toad).  28,400 X 7 = 198,800 pmpg.

That makes it 13.8 times more efficient at moving pounds down the road than the Prius.  Not bad for something with the aerodynamics of a huge brick.  And excellent for a house!

Presented 'tongue in cheek' but this does illustrate the reason OTR trucks are still economical.

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I'm glad that it was "Tongue in cheek". However, the MH does weigh ~9 x as much as the Prius and consumes ~6.5 times as much fuel so the Prius is only 72% as efficient as the HM............. SO!!!!! Point well made.......  ;D. We should all drive our MHs back & forth to work.

back in the late 70's I worked for a company that converted their fleet of medium duty (F600) work trucks to dual fuel system LPG/gas  because of the rising gas prices and gasoline shortages.

The one thing the crews all noticed was the power level went down noticeably on LPG, the trucks were already at the GVW limits and were terrible at climbing hills fully loaded... so as a result we pushed the pedal down even harder.
yes we were hard on those trucks trying to get the job done, and as a result it was noticed that we blew up a lot more engines than we did normally.

now maybe those blown engines were real clean inside,.... but they were still blown up.

The math isn't wrong.  It's the assertion that's nonsense.  It was presented purely as humor but 'someone' didn't catch that part.   

What is it Mark Twain said?  There's three kinds of liars: liars, damn liars, and mathematicians.

I wouldn't drive my motorhome to work for a dozen reasons, but I did use it to camp in the parking lot when I had to be on site 24/7.  Does that count? 

I once asked my DW at what fuel price she would park the motorhome permanently.  Her answer was "Wouldn't".  So it is one of those it is what it is things.

But wouldn't it be nice if this was 'real':

First off, a lot of people don't know WHAT they get in gas mileage because they don't keep accurate records.

I happen to be one of those fools that does keep a log of mileage and gas bought and I note each time whether I have filled it up to the top or not.

I am in a 1994 Class C with  Ford 8 cylinder, E-350. I am probably loaded to the max since I live in mine fulltime and I drive with a full tank of gasoline as well as a full tank of water. My gas tank rarely ever sees anything below a half tank.

I like my creature comforts. I want plenty of water and gas in case I end up broke down or lost or both. If there is a power outage at the campground or I am boondocking, I want plenty of gas in the tank for possible generator use. Even now, while workamping, I keep my tank filled to the top. I just never know when the power could go out, or a disaster strike and I want a full tank of gas to start my journey, whether I am leaving suddenly or on a planned trip.

My highest Miles Per Gallon in 4 years has been 9.5 and my lowest has been 6.6. Now then part of the problem is my gasoline generator runs off the same tank. I use my generator at least once a month and more often in the summer since I have a doggy and I need to keep him comfy when I stop to shop or sightsee.

The low of 6.6 MPG was going through the mountains with both the generator and the dash air conditioning running. I had friends traveling with me and we did this to keep everyone comfy. That's the worst MPG I have gotten and it does include the generator usage and we were climbing a lot of mountains.

My best was 9.5 and frankly I can't tell you if I had a strong tail wind or what, but I do top 9 MPG now and then. I do not tow a car, so I drive my RV for running errands, so probably half my mileage is stop-and-go and the other half is highway miles. I drive sedately to keep my engine and brakes happy.

When I do the math for a solid year between one full point and the last full point, my average for the past year was 8.3 MPG. My hourly meter on the generator works erratically, so I just have no real idea exactly how many hours I ran the generator, but it was run at minimum an hour a month and most months a lot more.

When I plan my trip budgets, I figure up the miles I might do then double that in case I change my mind, get lost, detour and so on. Then I assume 6 miles per gallon and a high cost of gas per gallon for the areas I plan to travel and set aside that much for gas for the trip. Needless to say, I typically have leftovers in the gas fund, which is the way I like it.

When money is tight, I've discovered that nailing down a ton of miles does not mean you see a ton of beauty. You can do a lot less miles and see a lot more along the way. Also, I stay longer in my favorite places to soak up all I can in that area. Sometimes I stay in parks just 30 miles apart but still I enjoy myself immensely.

Miles per gallon was not my sole criteria in choosing a motorhome. I chose one that could double as my errand transportation as well as had a lovely layout I found very workable for my fulltime lifestyle.

Good luck in your hunt.

I wouldn't believe anybody's gas mileage guesses unless they have a log book to back up their figures. I happen to have a log book to back mine up, for what it's worth. It's not entirely accurate because of the generator sharing the same tank and my generator notes are not that accurate but my mileage and gas fills are accurate.

A the last RV show, a sales rep said I could haul a 38 foot 5th with my short box RAM 1500. No problem ! These guys should be made libel for what happens next..

BTW, rounded of course, 3.8 litres = US gallon , 4.6 = Canadian gallon.

And the magic number for boats that has never been achieved is 2 mph...and I think that is US.

The new Challenger Hellcat goes through 1.5 gallons (US) a minute when using the loud petal   maked the 7-7 mph loo good..