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Old 06-16-2013, 06:48 PM   #1
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Is this amazing or what??

After owning the Berk since last November, I've finally gotten it on a real trip in the flatlands. Currently heading East on I-80 across Nebraska.

Now I drive pretty slow usually around 58 MPH. If the computer is correct, I'm averaging 15.2 MPG!!! This was with the AC off and no head or tail wind.

If this is correct, then I'm more excited than ever to have bought this coach. Between Durango and Denver in heavy mountainous driving I was getting 10+.

Now I know that aerodynamic drag increases with the square of the speed. In other words, double the speed the drag increase by a factor of 4. Triple the speed, the drag increases 9 times.

I know most all of you will not drive as slow as I do (it's just not in the average persons genes to go slow), but I'm retired and have nowhere to go and the rest of my life to get there.

Boowho?? (HUGE "stuff" eatin' grin on my face!!!)
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Old 06-16-2013, 08:06 PM   #2
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That is amazing! Are you towing? GOOD FOR YOU!
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Old 06-16-2013, 09:05 PM   #3
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That is amazing! Are you towing? GOOD FOR YOU!
I am towing, Milke..... but a Ford Fiesta only about 2600 lbs, I think.

I do know that with a vehicle with such a huge frontal profile (like a MH), that the drag thing I mentioned does come into play a lot more than with a streamlined vehicle. I just did not know it would make THAT much difference.

As a test, I may have to kick my speed up to 70 tomorrow, and see how much difference it makes.

BTW, as a matter of trivia, the MOST streamlined shape in nature is a rain drop (un-driven by wind). So, I was taught in HS MANY years ago.

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Old 06-16-2013, 10:25 PM   #4
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when i'm on the open road with no traffic, i avg 70 with no tow and my computer reads 8.5mpg with the -60. but so far i have only been driving about 1 hr from my home to the campground so it really is half streets half highway and not displaying my real highway mpg. i suspect i'm closer to 10 mpg on the highway.

that is AWESOME you are getting that good mpg boo!
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Old 06-17-2013, 08:36 AM   #5
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I'd love to see some hand-calculated numbers to see how that matches up with the computer. They're pretty impressive numbers!
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Old 06-17-2013, 01:27 PM   #6
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I just got back from a two week trip I left from Denver to Las Vegas and then in to Disneyland and back and the computer said I was geting 8.4 avg. That is with a lot of mountain driving and doing 70-75 on the flat highways.
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Old 06-17-2013, 10:03 PM   #7
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It's getting stranger!!!

Folks, today I was only able to manage about 12.2 MPG. I'm thinking that in leaving eastern Colorado and coming into Nebraska, I was running downhill even though the road SEEMED to be level. Eastern Colorado/ Western Nebraska elev is in the 4000 ft elevation range. Central/Eastern Nebraska is probably around 1000 ft elev. So it had to be at least a little downhill, right??

The other issue is that I MAY have had a tailwind, although I didn't think so. The 12.2 I got today, is pretty much what I expected in the flat lands. I was stunned with yesterdays figure (over 15), myself.

I find something interesting with the FL computer with regard to MPG calcs. I've been getting up to my cruising speed and then do a reset. On my toad the MPG reading begins immediately increasing rather quickly until it reaches the current average MPG.

On the FL, the display is reset, but it's 2-3 minutes until it starts updating. But this is really weird: as the MPG climbs, it will instantly drop back and then begin climbing again.

For example, today is climbed up to 13.2 and then instantly dropped to 9.8.... Started climbing again to 13.2 then instantly dropped back to 9.9.

It repeated this dance 10-12 times until if finally settled down to 12.2. Each time it repeated, the point it dropped back two was a little higher than the previous time. Like 9.8 then 9.9 then 10.1 then 10.3, etc.

And no, there was no difference in the way I was driving, no hills, no nothing that could have caused this weird behavior.

I'm fascinated by all this and I plan to keep experimenting to see if I can figure it out. I'm going to do a manual calculation (as one of you mentioned) the old fashioned way to see how accurate FL's computer is.

Boowho??
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Old 06-17-2013, 10:33 PM   #8
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lol.. i think you need a computer like the silver leaf system boowhoo. lol
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Old 06-18-2013, 07:57 AM   #9
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lol.. i think you need a computer like the silver leaf system boowhoo. lol

Yeah, I'm getting so confused, I don't know whether to wind my a** or scratch my watch!!!

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Old 06-18-2013, 08:24 AM   #10
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Mpg

boowho,
If I remember correctly you had some problems with the mode control it was replaced or reprogrammed I do not remember which. You said you usually travel at 58 MPH (boy you must have some control), did you ever get in 6 th gear?
GOOD LUCK
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Old 06-18-2013, 08:25 AM   #11
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We just returned from a 2700 mile trip. With the generator running both a/c's, towing a CRV and average highway speed of 75mph we averaged 9.5mpg.
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Old 06-18-2013, 09:03 AM   #12
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BTW, as a matter of trivia, the MOST streamlined shape in nature is a rain drop (un-driven by wind).
Hmmm...
I always thought it was Angelina Jolie.
Who knew.

Doc
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Old 06-18-2013, 09:05 AM   #13
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Hmmm...
I always thought it was Angelina Jolie.
Who knew.

Doc
Jennifer Aniston I heard
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Old 06-18-2013, 10:33 AM   #14
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Jennifer Anniston I heard
No argument there!
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Old 06-18-2013, 12:18 PM   #15
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We have a 2013 390BH-40. I have been amazed at the fuel mileage. We are in Texas and drive mostly flat highway. I cruise between 65-70 and find there is a significant difference in mileage with only a slight difference in speed. At 65, I'll get 12+, at 70, closer to 11, while at 75, down to 9.5 or 10. We are not towing, but are over GVWR by about 1000 pounds. And it has been very windy so far this spring. I have hand checked the computer many times and find it to be very accurate. In fact, if you turn it on the mode to show how many gallons you use, it is right on, unless the generator is running. When our genny is running with both a/c units I allot about 0.75 gallons per hour. Before I bought it, I was expecting 6-8mpg, so am thrilled with this performance.
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Old 06-18-2013, 03:53 PM   #16
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We have a 2013 390BH-40. I have been amazed at the fuel mileage. We are in Texas and drive mostly flat highway. I cruise between 65-70 and find there is a significant difference in mileage with only a slight difference in speed. At 65, I'll get 12+, at 70, closer to 11, while at 75, down to 9.5 or 10. We are not towing, but are over GVWR by about 1000 pounds. And it has been very windy so far this spring. I have hand checked the computer many times and find it to be very accurate. In fact, if you turn it on the mode to show how many gallons you use, it is right on, unless the generator is running. When our genny is running with both a/c units I allot about 0.75 gallons per hour. Before I bought it, I was expecting 6-8mpg, so am thrilled with this performance.
I'm surprised at the genset using that much per hour. When I drove 18 wheeler, the companies used to grouch at the drivers for idling all night to keep warm (or cool) because they said it burned about 1 gal per hour; and that's a 500+ HP engine.

One company actually installed auto-start on all their engines and tied it to the inside-the-cab thermostat. The engine would start and stop many times over night and even though the auto-start systems were quite expensive, they felt they saved a lot of money over time.

Oh yeah, each time the thing shut down the whole truck shook like a dog that just got out of the lake and would wake me up almost every time.

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Old 06-18-2013, 04:03 PM   #17
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boowho,
If I remember correctly you had some problems with the mode control it was replaced or reprogrammed I do not remember which. You said you usually travel at 58 MPH (boy you must have some control), did you ever get in 6 th gear?
GOOD LUCK
AREA51

Yes A51, I did get the mode thingy fixed and easily run in 6th at 58 mph.

As far as "control".... Like I said, I have nowhere to go and the rest of my life to get there. The older I get the faster other drivers seem to want to pass me!! I imagine I aggravate a few, but I try not to by pulling over when a long line gets behind me on a two lane road (for example) and NEVER driving slow in the passing lane.

Driving slower puts a lot less wear and tear on the vehicle. For example, I usually get about 70K miles out of a set of brake pads(shoes). And of course your mileage will be better on almost any vehicle, but especially so on a high frontal "footprint" vehicle (like a MH)

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Old 06-18-2013, 04:39 PM   #18
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The Genset usage is specified by Onan in the manual. It's 0.49 gph at half load and 1.02 gph at full load. Both A/Cs running is more than half, but less than full. That's where I came up with the estimate. It seems to mesh pretty well with hand calculations at the pump.
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Old 06-18-2013, 11:11 PM   #19
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The Genset usage is specified by Onan in the manual. It's 0.49 gph at half load and 1.02 gph at full load. Both A/Cs running is more than half, but less than full. That's where I came up with the estimate. It seems to mesh pretty well with hand calculations at the pump.
Thanks... I guess that little engine is working harder under full load than a 500+ HP one does at idle. Amazing.... I learn more and more the older I get.

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Old 07-17-2013, 07:44 PM   #20
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2300 miles and change from northeast PA to Bozeman MT and I have at 9.9 mpg for the trip. Thats fabulous! Cant wait to see what i get when the engine is broken in. Cruise has been set at 62 and I am towing a Chevy Equinox.
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