How do I maximize MPG? from miles per hour

[mikeleblanc413]

I've been so very lucky to have this incredible teaching opportunity come my way...I'll be teaching the children who travel with the Carson and Barnes circus...shortly, I'll be leaving Texas for Wyoming to meet with the circus...in your experience, what miles per hour has maximized miles per gallon. I have a 2000 Winnebago Minnie Winnie, V-10, total weight is 1500 below maximum...all thoughts appreciated.

[pianotuna]

Hi Harvard,

US gallons. Local fuel prices are as much as 5.266 per US gallon.

I do have air tabs--but all they seem to do is make the RV quieter (i.e. less wind noise). If I am traveling in the same direction as the wind I do get better mileage with the tabs. Against the wind it is still drinks fuel just as before.

I'll very shortly be going to larger tires. (215 R70 16 up to 235 R85 16) I'm hoping that will make a slight improvement. It will most certainly improve my lousy ground clearance. I did finally get a huge caster which I use in the oem hitch to "stop the grind".

[Harvard]

pianotuna wrote:
Hi,

My class C v-10 weighs in at 14,000 pounds. If I drive 48 mph I get between 10 and 11 mpg. If I drive 50 I get between 9 and 10 mpg.

Is that Imperial Gallons or US Gallons?

[Rolin]

My experience is:
Use Scan Gauge to monitor instantaneous MPG and average MPG. Its sort of a game to find what driving actions give the best mileage. There was one display that would give an idea of what load transmission downshifts out of lockup.

55 to 60 mph seems to work best - depending on conditions.

Try to keep the transmission locked in highest gear by slowing as you go up hills.

Keep tires inflated properly, I inflate a little above the MH mfg recommendation, rides rougher but helps on mileage. Actually older tires get better mileage as there is less sqirm in the tread. I call them broken in tires.

Make sure your air intake filter is clean.

In some cases traveling with the trucks (18 wheelers) helps as these large vehicles traveling in the same direction create their own positive wind. Not advocating tailgating, Just following at a respectful distance (you don't have to be real close to benefit). I don't follow the fastest trucks..I pick those who seem to be mindful of managing fuel economy.

Check out some of the hypermiler or ecomodder websites. They have some interesting ideas. Of course a lot of them don't apply to motorhomes but some do.

MPG awareness keeps you in-tune with your surroundings, the weather, geography, road conditions, traffic, looking forward, etc. In the moment, except when I'm daydreaming.

Sorry, that was a lot more than you asked. As my DW says...didn't want to know how the clock was made, just wanted to know what time it was.

[ron_dittmer]

ronfisherman wrote:
Invest in a ScanGauge II. It will show what the best speed is to run at. I have had one on my motorhome for years. After finding out what works best. You may never use Cruise Control again.

I just installed a Scanguage-II but yet to have gone on a trip to see what is learned.
Given the price per gallon of gas, I anticipate the $160 to purchase the SG-II could be recovered within the first 5000 miles.

I installed it on top of my backup camera monitor as seen here.

[skipnchar]

The main REASON you get better mileage at slower speeds is because of the wind resistance. For that reason your optimal speed/mileage combination will change depending on wind direction. It will PROBABLY be slower than you want to drive on the highway when winds are on the nose. Best you can hope for is to just go slow enough that you get as much fuel economy as you can STAND to get for the driving you're doing. MOST of the time your actual optimal speed will be around 20 MPH.

[ronfisherman]

Invest in a ScanGauge II. It will show what the best speed is to run at. I have had one on my motorhome for years. After finding out what works best. You may never use Cruise Control again.

[tpi]

Ron is certainly correct as it pertains to the V10 driveline. In mine there is all kinds of unfavorable cruise control actions pertaining to fuel economy. One example would be attempting to maintain speed on a steep hill, the throttle is opened and the transmission downshifts to 4000 RPM. Driving without cruise control you can let the speed gradually scrub off, avoid the downshift, and keep RPM down. Another behavior on my cruise control is the downshift on downgrades in an attempt to keep speed from running away. Of course the driver knows best and letting 5-10 mph speed buildup on a downgrade may be be completely OK and it would improve fuel economy.

Keeping the speed somewhere in the 55-60 MPH range is probably the best overall tip. Coasting to stops is another one.

[ron_dittmer]

Nomadac wrote:
........I disagree.......

The topic of discussion is the OP and his class-C Ford E350/E450 with gasoline V10.

Actually I would think there will be variances in given advise between an E350 and an E450 chassis because the gear ratio flavors in the differential....weight of rig....also whether towing or not, whether a B+ or C. Lots of variables with an E-series-V10 that influence how to achieve ideal fuel economy.

[Nomadac]

ron.dittmer wrote:

Using cruise control is bad news for fuel economy because it will go full throttle up every over-pass, and then engine brake down the other side. I wished I could set the throttle to a window of variance to let the rig slow down some up hill and coast fast down hill.

I disagree, as I use my CC on hills and have found it to be more effective than the driver in selecting the best speed, transmission gear than most drivers. My MH coasts down hill and the Allison Transmission operates better that most drivers, IMO.

Maybe in your Class C, but in a DP that is not true. I can monitor the engine RPM going uphill and down hill and monitor gear,etc.

[pianotuna]

Hi,

My class C v-10 weighs in at 14,000 pounds. If I drive 48 mph I get between 10 and 11 mpg. If I drive 50 I get between 9 and 10 mpg.

[Sloop_Smitten]

One way to determine your most optimal speed for fuel savings is to install a vacuum gauge. Monitoring your vacuum will allow you to maximize your engines efficiency.

Check out this link: Popular Mechanics Article

[Nomadac]

Drive like you had an egg between your foot and the gas pedal. Avoid fast starts, 60-63 MPH on Interstates, use cruise control, keep tires properly aired, engine properly maintained, including air filter, avoid city traffic when possible.

The best fuel mileage is driver controlled.

[ron_dittmer]

I agree with all above.

55mph +/- 5mph pending. Take advantage of a good tail wind by going 60mph. But a head wind try to maintain 55mph, but don't force a particular speed. Don't fight wind or inclines. Let the rig slow down some, but don't become a road hazzard either. I watch which way and how much tall grass far off the road is leaning. It's a good guage on wind speed and direction.

It helps to drive stocking footed to feel the pedal better to determine how far down you are pushing it.

Using cruise control is bad news for fuel economy because it will go full throttle up every over-pass, and then engine brake down the other side. I wished I could set the throttle to a window of variance to let the rig slow down some up hill and coast fast down hill.

[Dick_B]

There are some other tricks like taking off Cruise Control when going up a steep hill other wise the CC will try to maintain the 55 mph and pour the fuel into the engine to try to do that.
Don't try to be the first one off the starting blocks at traffic lights. Coast into stop lights, like the truckers do, so you don't have to come to a complete stop.
There must be others...

[Coalminer_UG]

55MPH