MPG to expect

[Mark R.]

This thread needs to be interrupted with a feel good sanity post.

My DP gets 11 MPG solo, 10 with toad at 60 MPH, now for the feel good part, my boat gets 1.2 MPG at 10 MPH and 4.5 gallons per mile at 20 MPH!!!

Feel better about 7.5 MPG now?

 

[DonTom]

now for the feel good part, my boat gets 1.2 MPG at 10 MPH and 4.5 gallons per mile at 20 MPH!!!
Feel better about 7.5 MPG now?

Not until you tell me what MPG your boat gets when going the same direction as the current. Will that be worse than a RV going downhill?  ;D

-Don- SSF, CA​

 

[Mark R.]

Will that be worse than a RV going downhill?  ;D I assume you meant uphill.
I think my boat does get worse MPG at 10MPH then my coach does going up hill with toad, and the hill ends in a few minutes but the river is long so the MPG stays bad  as long as its running.

 

[mrschwarz]

The only long trip I have made showed me 10 mpg on the engine computer. That was driving all day on the interstate. When I go on shorter trips, the computer tells me I get between 8.5 and 9(.5). My engine is only a 6.7l which I have been told gets better mileage than the larger block.

 

[Kevin]

The only long trip I have made showed me 10 mpg on the engine computer. That was driving all day on the interstate. When I go on shorter trips, the computer tells me I get between 8.5 and 9(.5). My engine is only a 6.7l which I have been told gets better mileage than the larger block.

Do you ever just check it with the milage, gals put back into the MH? our computer showed that we were getting 8 once, and it was really about 6, then it showed 4 once or twice, and it was really about 6.5.

 

[Gary RV_Wizard]

The computer mpg readouts are notoriously optimistic, but usually only  a few (or several) tenths rather than 1-2 mpg. Manually calculating mpg by tracking gallons purchased vs miles actually driven over several thousand miles is the only way to get areal handle on your mileage.

The Cummins ISB (5.9L or now 6.7L) is quite fuel efficient, but it is also used in lighter or shorter RVs and that helps too. The Cat 3126 is another miserly engine.  Not surprisingly, it takes more fuel to feed the 8.3 and 8.9L big block engines that are driving the 34k-40k lb 40-45 footers.

Fuel economy also took a downward step when the new EPA regs for diesels went into effect on 1/1/2007.

 

[Kevin]

Roamer, If just excepted the fact that I get...at best 6.8, at worst...4.4 and usually I end up getting 6.5 I've tried the 65mph thing, I've tried the 70mph, and 75, but I just can't seem to get the 8mpg or the even the 7mpg that I hear about :-\ So as long as  I know that going into this, I'm ok with it..well sort of ???

Ps love the new faces