MPG to expect

[shavergator]

Just curious about miles per gallon. What can you expect to get on a Ford V-10. Mine is in a 34 foot ( 2000 ) Monaco Monarch. I know there are many factors that affect miles per gallon, but what is a good average to expect averaging 60 on the highway. And what would a comparable diesel average ?

[Mc2guy]

YRMV, but it would seem that 6.5-8.0 mpg would be the norm for this engine and body size.  I have been averaging about 7.5 in a 2009 Winnebago Sightseer 35J.  I have not owned a diesel, but most seem to report 9-10 for an equivalent model. 

[DonTom]

Just curious about miles per gallon. What can you expect to get on a Ford V-10. Mine is in a 34 foot ( 2000 ) Monaco Monarch. I know there are many factors that affect miles per gallon, but what is a good average to expect averaging 60 on the highway. And what would a comparable diesel average ?

My guess is that you will average about 7 MPG at 60 MPH. If it were a diesel, I would expect you would get around 10 MPG.

                                             

    -Don- SSF, CA

[FrontrangeRVer]

We had a 1999 Holiday Rambler Vacationer 36' motorhome with the V-10, and we got 6.0 - 6.5 mpg.  I wasn't easy on the gas pedal either, so you could possibly get 7.....

[RV Roamer]

I'd say 7.5-8.0 if you have a light foot, around 6.5-7.0 if not. Towing a car typically impacts a gas chassis by up to 0.5 mpg., so those numbers might increase if you do not have a toad.

[Wizard46]

My 2002 Brave 34' gets about 6.5 to 7 on Florida Interstates with my driving. I could probably get a little better if I slowed down, but probab,y not more than 7.5 and then I would be afraid of getting run over !!!!!

[sheltie]

My 2002 Brave 34' gets about 6.5 to 7 on Florida Interstates with my driving. I could probably get a little better if I slowed down, but probab,y not more than 7.5 and then I would be afraid of getting run over !!!!!

Not trying to throw fuel into the fire, but I have a different question.  Why, after one has spent a very significant amount of money to buy a mid/big rig would anyone worry about the mpg?  You know going in that you will get a small range of mpg, regardless of the gasser engine, so why worry?  Even if one increases mpg by 2 mpg (unlikely), the saving per tankful is insignificant when considering how much you originally paid for your rig.  Don't obsess, just enjoy.

[DonTom]

Even if one increases mpg by 2 mpg (unlikely), the saving per tankful is insignificant when considering how much you originally paid for your rig.

There are other reasons. One that's important to me is how far the vehicle can go on a tank of gas. There are still many routes  that are more than 100 miles between gas stations and then when you get to the next gas station, it's closed for whatever reason. That 2 mpg would get you another 100 miles with a 50 gallon tank.

-Don- SSF, CA

[shavergator]

Thank you all for your ideas. I would say 7mpg is about right.  How much change would you expect when running the generator ?

[DonTom]

Why, after one has spent a very significant amount of money to buy a mid/big rig would anyone worry about the mpg? 

Because after spending "a very significant amount of money to buy a mid/big rig" they might not have enough money left to make the payments if they get a poor MPG .

-Don- SF, CA

[RV Roamer]

How much change would you expect when running the generator ?

A typical generator will consume 0.5 gal per hour at about 50% load. That's probably more than your actual load if running just one a/c. The genset manual will likely have an estimated fuel consumption.

[tallyo]

There are other reasons. One that's important to me is how far the vehicle can go on a tank of gas. There are still many routes  that are more than 100 miles between gas stations and then when you get to the next gas station, it's closed for whatever reason. That 2 mpg would get you another 100 miles with a 50 gallon tank.

-Don- SSF, CA

 I learned a long time ago never to see how far I could stretch a tank of fuel..... Generator won't run when tank is below 1/4, if yer ever stuck someplace without a hook up you may need some fuel just to beat the heat. If yer ever in a campground that loses power for any time period .. well you get the drift.....

I always start looking for a fuel stop when I get near the 1/2 tank...... I call my travels a "half tank trip"

[scottydl]

I always start looking for a fuel stop when I get near the 1/2 tank...... I call my travels a "half tank trip"

And I don't know about anyone else, but when my gauge reads at the 1/2 mark, I really only have about 1/4 tank left anyway!  Every vehicle I've ever had has artificially stayed on/near "Full" longer than it should, then the needle drops like a brick.  Of course the RV has many more reasons why it's not a good idea to potentially run out of gas while who-knows-where out on the road.

[Mc2guy]

My gauge seems to have five 15 gallon increments.  Past F to F is 15 gallons, Full to 3/4 is 15 gallons, 3/4 to half is 15 gallons, and half to 1/4 is 15 gallons.  I have tested each increment with the scan-gauge and with a fill-up and they seem spot on.

[tallyo]

And I don't know about anyone else, but when my gauge reads at the 1/2 mark, I really only have about 1/4 tank left anyway!  Every vehicle I've ever had has artificially stayed on/near "Full" longer than it should, then the needle drops like a brick.  Of course the RV has many more reasons why it's not a good idea to potentially run out of gas while who-knows-where out on the road.

So much depends upon the shape of the fuel tank. If it's fatter at one end ( top or bottom) then the readings can be affected. I always find the guy who says he's getting many mile per gallon  is figuring at the 1/2 tank reading or is using the MPG reading off the dash board and is not using actual gallons used at refill time.....

After so many years and so many fill ups, I just keep pumping , paying and enjoying the ride....

[scottydl]

Not trying to throw fuel into the fire, but I have a different question.  Why, after one has spent a very significant amount of money to buy a mid/big rig would anyone worry about the mpg?

I always keep track of mine (1) because I'm curious, (2) because I like to see how different circumstances affect or don't affect the mileage so I *can* maximize (even by just a little) if reasonable, and (3) because if the average ever REALLY decreases it can give forewarning of a mechanical problem that might otherwise go unnoticed and lead to something worse.  Just a few reasons. 

[DonTom]

I learned a long time ago never to see how far I could stretch a tank of fuel..... Generator won't run when tank is below 1/4, if yer ever stuck someplace without a hook up you may need some fuel just to beat the heat. If yer ever in a campground that loses power for any time period .. well you get the drift.....
I always start looking for a fuel stop when I get near the 1/2 tank...... I call my travels a "half tank trip"

Is that the generator won't start below a quarter tank fairly standard in RVs? I had no idea that they made RV's that idiot proof. 

Another reason to want a lot of gasoline in the tank at all times is for the fuel pump. The gasoline helps keep the fuel pump cool and it will last longer when it's all in the gasoline. It runs hotter when the tank is near empty. To have a fuel pump replaced can be an expensive job in a RV.

BTW, the best MPG I ever got in my old 22 foot class C (1978 400 CID  junk small block, but with MPFI <modified by me> ) was when I was driving in Yellowstone all day with very low speed limits. Got just over ten MPG at an average of 30 MPH or so.

The modification I did was from here.

-Don- SSF, CA

[RV Roamer]

Is that the generator won't start below a quarter tank fairly standard in RVs?

Yes, but the nominal "1/4 tank" can have a wide variance, depending on the whim of the guy who installs the generator fuel line into the tank. Consistency is NOT a hallmark of RV production.

[DonTom]

Yes, but the nominal "1/4 tank" can have a wide variance, depending on the whim of the guy who installs the generator fuel line into the tank. Consistency is NOT a hallmark of RV production.

That's nice to know as I had no clue about that and I probably would have tried to fix something that's not broken if I ever let my gas tank get that low.

BTW, something I was curious about. Where's the fuel pump located for the generator? Is it in the generator itself, or somewhere on the fuel line, or in the gas tank? Or again does it depend on who designed the RV?

-Don- SSF, CA

[Kirk]

We have owned our Ford V-10 chassis motorhome now since it was new ten years ago. At first we were getting about 7 mpg and the difference when towing our Ford Ranger and not towing was hardly detectable. After about 18 months of this we had the complete Banks upgrade put on with the TransCommand unit for the transmission. This system greatly improved our performance and since we keep the right foot light, that increase in power has also gained us a significant improvement in mileage. We now typically get around 8 mpg, and 8.5 is not uncommon and that is always towing, because we are fulltimers.

[RV Roamer]

Where's the fuel pump located for the generator?

Probably depends on the generator make and model. Since the generator is designed and installed separate from the chassis and fuel tank, I assume it will have its own fuel pump rather than in the tank, but it could be external (on the fuel line) or bolted to the genset itself.

[Lou Schneider]

Usually the generator is supplied as a package, complete with enclosure,etc.   The fuel pump is part of this package.  Look for a little square module in the fuel line.

[DonTom]

Usually the generator is supplied as a package, complete with enclosure,etc.   The fuel pump is part of this package.  Look for a little square module in the fuel line.

You mean the fuel line after it gets into the generator? I think I would have to take the generator out to find it. But it must be there, because I could not find it anywhere on the fuel lines under the RV. I checked a few days ago when I was last at my Reno home.  I will have to look at the generator manual again.

                                                                                       

-Don- SF, CA

[mdbass]

I agree with the "never let it get below a 1/2 tank" rationale. Not championing for diesels; but I had one gas rig and that cured me-6.5 mpg tops! All my diesels have gotten 10-11 to the gallon. I understand the rationale for wanting to know mpg, but I also agree it's sorta mox nix after a while. I figure it costs me around $100-$125 a day to RV-and that's driving. (It probably got higher when diesel went to $4.00 a gal) We've been down this road many times before. Today its even more topical-have you checked the cost of hotels and eating out lately? Obviously, I love our coach, but I'm not trading for a hotel room anytime soon. Our opinion-go with a diesel with a slide. We fulltime now; but used one every other weekend or so for years and it worked just as well.

[kevin]

10-11mpg WOW

[maryland-david]

wll I have a pretty big Cummins and weigh around 50,000# with Toad and get between 6-7MPG. I thought that I would get better than that and I have a light foot.

[mdbass]

We dropped to 9.5 - 10 mpg last trip- 1300 miles with a toad. It can be done. BTW we are governed to 1850 rpm-(65 mph) and average somewhere in the mid 50 mph range according to our gps. We stay in the right (granny) lane and mosey along. The return in fuel savings more than justifies it. If you want to try this, make sure your mechanic adjusts the rail pressure when he governs the rpm. That way you don't lose your low end grunt.

[mdbass]

Maryland David-We have the small Cummins in a HR Endeavor. We also weigh a lot less than you. Geez-we're barely pushing 30,000 pds. Also; if you have a newer RV, it's probably controlled by several computers (like the DDEC system in Detroit engines). It really behooves you to use the cruise as much as possible if this applies to you as it is designed to maximize fuel consumption. You can also get a wealth of information from the computers (your mechanic can download it or you can purchase the adaptor to connect your PC or laptop to the onboard computer (via the PROM). Believe me, you won't be able to digest it all. It can help you with your fuel consumption.

[kevin]

Not to start a fight, but how on earth do you not get run over on the interstate? you must be doing30 on the big hills too? I guess if that is what ya gotta do to get 9-11mpg then so be it,but I just can't run that slow

[maryland-david]

Maryland David-We have the small Cummins in a HR Endeavor. We also weigh a lot less than you. Geez-we're barely pushing 30,000 pds. Also; if you have a newer RV, it's probably controlled by several computers (like the DDEC system in Detroit engines). It really behooves you to use the cruise as much as possible if this applies to you as it is designed to maximize fuel consumption. You can also get a wealth of information from the computers (your mechanic can download it or you can purchase the adaptor to connect your PC or laptop to the onboard computer (via the PROM). Believe me, you won't be able to digest it all. It can help you with your fuel consumption.

Yeah even with my extra 20,000#, I was expecting 7-9MPG. I have over 2 million miles driving big diesels and I have always gotten great fuel mileage. I just have not found a sweet spot for my combination. Of course I think that gap in the Allison 6 speed is too big. I ran 13 speeds and 18 speed transmissions most of the time. I am probably even dating myself but even drove a 6x4. At 65-70MPH I am near 6MPG. At 55-60MPH I am closer to 7MPG.