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Tajfish 01-15-2019 10:05 PM

2007 Bounder diesel 38 towing Suburban 2500 4x4 and usually drive 65 mph. I have been running 7.6 mpg on avg. Just had full service on the 300 hp Cat and hope to break 8. Had a Pace Arrow with 454 and got 8 mpg. Also had a 2003 Discovery with the 300 cat and pushed 9 a time or two. I think 8 is normal for good in a 38 - 42 ft house on wheels.

saddlesore 01-15-2019 10:39 PM

'02 Foretravel 40', mdl-320 with tag
ISM 450/500, 4060r Allison with retarder.. TX geared
(long legged.. shifts into 2nd overdrive @ 65/67mph )
7 to 8.5 mpg depending on terrain & % of bio-fuel mix, no change when towing (2,400 lb toad, 4 down)

96 Wideglide 01-15-2019 10:56 PM

6 to 8.5 depending on how many mountain ranges I am going over.

Bubba1 01-15-2019 11:13 PM

Entry level 36 footer, 300hp Cummins 5.9, Allison 2000MH trans (5sp). Get 8 to 10 mpg depending terrain and wind. Towing 3300lb towed.

Mike H

desertdd 01-16-2019 07:08 AM

I always thought if you want to own a motorhome there are bigger fish to fry then fuel mpg.

nathaniel 01-16-2019 02:26 PM


jimmy braden 01-16-2019 05:13 PM

well, yes but there is some value in base-lining the nominal fuel use..

But the biggest variables are ( as was said in post ): engine displacement, weight, boost and normal traveling speed.

So if you dont have some reference point to your config, its hard to make any real info transfer.

Just get VMSpc and it is your friend. It will tell you instant MPG and a rolling trend

Scottybdivin 01-16-2019 05:19 PM

07 Mountain Aire 4528, 450 ISM, towing F150 CC, 5.5 - 7 depending on all the variables. 6.5 average over 22k mi.

ClassAboater 01-16-2019 05:52 PM

This is an interesting thread...

We drive a Fleetwood Terra LX 32 with a Ford V10 engine. Normally set the cruise at 62 MPH (per GPS) on the highway and average 8MPG. This is pretty close to the same as the diesel pushers of much larger vehicles.

spsm 01-16-2019 05:53 PM

6.5 maybe 7. 400 ISL. 62-65 mph. 2003 MA

saddlesore 01-16-2019 07:41 PM


Originally Posted by desertdd (Post 4591847)
I always thought if you want to own a motorhome there are bigger fish to fry then fuel mpg.

Yup... I did not buy the Shack just to stress about how much fuel is used....They are big,heavy and have the aerodynamic's of a fat brick..

jacwjames 01-16-2019 08:13 PM

First year we had the coach we went to Alaska driving +14K miles, averaged 8.3mpg including generator use. Did not pull a toad.

Bought a toad, 2005 Jeep GC.

I now average ~8 mpg, so not much difference.

I did invest in a Silverleaf VMSpc system and it is very accurate compared to manual calculating the mpg.

Smitty77 01-16-2019 09:25 PM

About 37K Lbs when fully loaded for travel, and with our CRV weight being towed behind us. 40' coach with tag, ISL370 (Now 400) CAPS era engine, just over 72K miles. Silverleaf reflect 7.9MPG life time usage, 3-4 years ago it was 7.4MPG. Changes of tires, source engineering wax valve, and possibly FASS fuel pump, and probably the engine finished breaking in - all have resulted in the last 3-4 years of steadily improving overall MPG.

I'd suggest for budget planning, to use the MPG range that Scott provided, as he said - that keeps it simple, and gives you a range to know potential low/high MPG averages. Now the real question, is what will the fuel prices be:)!

Best of luck to you,

FatChance 01-17-2019 08:08 AM


Originally Posted by FIRE UP (Post 4591584)
Simple answer, 5-8, done.

This ^

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