Community Forums

bobioknight · 06-23-2013, 09:32 AM

Yes, anything could have happened, but at this point it would have been the fueling, because from my house to napa is a certain distance, that does not vary. however the fueling could. I have another long trip coming up in August 860 miles round trip to yosemite. I will run the numbers again. I expect there are many hills to climb, which will hurt my mpg a bit more than the mostly flat run to napa. However, I will not be running with full tank of water on this trip either.

I have a feeling I just got lucky buying the right coach. Because 7-9 mpg would have put me below or at empty for the trip, however, I returned with the gauge reading between 1/4 and 1/2 remaining. When I refilled it took 65 gallons to top off. I guess maybe I did not top off as much as I could have possibly leaving some fuel off my numbers but doubt it could have been that much.

Yep, I think I just got lucky buying the coach I did, she is obviously broken in with rollen with some pretty good karma.

mel s · 06-23-2013, 10:18 AM

Quote:

Originally Posted by Coaster1

Surely you meant 8 MPG ?

X 2!

Bobioknight
You are either very fortunate, (or you forgot to include 3/4, or a full tank of fuel when you calculated your mileage).
My MPG has averaged 8.5 over 107k miles in 13 years.

When looking for my first coach, 28 years ago, I was told by an experienced coach owner, "If anyone tells you they get an "overall average" greater than 9 MPH with their class A diesel coach, (or 7 MPG with a gasser), they probably are lying about more than just mileage".
"Run, do not walk, to the next coach on your list".
Mel
'96 Safari

bobioknight · 06-23-2013, 05:40 PM

Hum, well, I would not intentionally lie or mislead anyone. Not sure what the point of that would be. Ok for the competitive skeptical members, you've got me, I really had to fill up 4 times. Using 440 gallons not 65. Yielding approx 3 mpg. Hope that helps y'all sleep better. Hehehe...

So should I be asking for pointers how to decrease mileage, because something must be wrong with my motor, I am not getting the national average of 7-9 mpg. I am wondering if anyone else is plagued with a higher mileage than 9 mpg.

greatlakes · 06-24-2013, 06:52 AM

Ive gotten 10mpg with mine but it was on a trip where a had a 10mph tail wind on Ohio flat ground and was on a two lane hwy where the speed limit was 55.

bobioknight · 06-24-2013, 08:03 AM

I retraced my route to and around napa, round trip was 963 miles and not what the odometer reads (1120 miles). Wondering does the odometer and speed come from front or back tires. So if I am running a little taller tire and have then aired up to the max would that cause this kind of difference.

Also more importantly to this conversation, i assume having the tires aired to their max would cause way less drag, you can actually look at the tires and visually see the difference in drag after airing them down to the suggested pressure. So, if I get extra fuel efficiency with aired up tires but sacrifice some of the life of the tire, would it be better to keep the tires inflated higher (not over max by the way), it seems losing some tread life on tires that on most RV's when replaced look like tread life was not an issue but age killed them.

mel s · 06-24-2013, 08:20 AM

Quote:

Originally Posted by bobioknight

Hum, well, I would not intentionally lie or mislead anyone. Not sure what the point of that would be.

bobioknight
No one said you intentionally lied or mislead.

I calculate MPG after every fill up.
Occasionally it will calculate @ 11 MPH but inevitably the MPG of the next fill will be low to make up for it.
I've used 12,570 gal of diesel in 106,840 miles.
I've never seen black smoke except for a puff at start-up.

I once met another Safari owner who claimed 11 to 12 MPG with his DP.
.....I also met a guy who claimed that his car got such great gas mileage that he had to carry an overflow can to catch the extra.

If I had a 17+ MPG diesel coach I wouldn't waste my time trying to convince other coach owners about something they can/will never experience.... I would contact Ripley or the Guinness World Record people.

Mel
'96 Safari, 134k miles

Brockx · 06-24-2013, 08:47 AM

Drafting can make a big difference, if you are serious about maintaining the draft. But; not a 100% difference.

My daily driver is a Ram 1500 with the 5.7 Hemi. I have 95k on it and it has always been capable of 14/15 urban, 19/21 highway, if driving normal speeds. I play around sometimes and put the instant read MPG feature on the trip computer and can see as high as 27 mpg in a tight draft. The trip computer is normally about 1 mpg optimistic when I compare it to miles/gallons.

Brockx · 06-24-2013, 08:54 AM

Just another thought: I track total miles/total gallons overall I'm at 7.4MPG.
However; my low was 3.83 high was 11.45, both cases due to bad angles at the pump.

greatlakes · 06-24-2013, 09:19 AM

The difference of a 41" dia tire vs 42" is 2.4% in circumference. So over your trip could make a difference of 26.8 miles on the odometer. Assuming you get a whole inch difference in dia from higher inflation.
Not really enough to account for a 7 to 8mpg gain.

Butte64 · 06-24-2013, 02:36 PM

Another thought is that when the diesel pump clicks off the tank is not full. There is quite a bit of foaming that goes on which makes it appear the tank is full.
If you go fill it now I expect you will find room for more diesel and putting that into your calculations will revise your figures. But even that should not make the difference between expected MPG and what you experienced.

We look forward to your future reports.

zeeyaarv · 06-24-2013, 02:56 PM

The only way our DP could get 17mpg would be to drive off the edge of the Grand Canyon and that would be for mere seconds. I wish my Wrangler toad would get 17mpg.

jimmyjnr · 06-24-2013, 03:09 PM

I suspect both cummins and cat would pay big money to get their hands on that engine

Rich-n-Linda · 06-24-2013, 09:43 PM

Quote:

Originally Posted by bobioknight

Ok for the competitive skeptical members, you've got me...

There is nothing "competitive" about this at all. And the comments from people like me are not "skeptical." We are telling you that your numbers are WRONG. That's not skepticism or opinion...it is a FACT. It is IMPOSSIBLE for a coach the size of yours to achieve an overall average of 17.3 mpg.

At some point soon you will discover your error. Then you'll understand.

B Bob · 06-24-2013, 10:00 PM

bobioknight - Murrieta is about an hour up the road from us. Our CC has nearly the miles you have on yours, but is a bit newer. We do not get near 18 mpg. More like between 7 - 8. I just had a new charge air cooler put in so I hope my mpg goes up a little.

Country Coaches are great motor homes. We have enjoyed ours.