2004 Dynamax Sport Sedan 220 mileage

I don't know much about the chassis that particular motorhome is based upon, but a couple of things come to mind which might have skewed your number to the lower side. Though, I'm tempted to say that 12-14 MPG is probably pretty optimistic if this is a gas engine motorhome.

That said, how long was your trip? Did you have to fill the tank several times, or are you basing your calculations on a half-tank of fuel? The more times you "fill the tank" you tend to average out the fact that tanks don't always fill to the same level everytime. If you base it on a single fill, you the pump may have kicked off early when you topped it off to leave, and then didn't kick off early when you refilled.

Also, what terrain were you travelling over? A lot of mountains, or mostly level?

Was your trip recent? If it was during a cold snap (we've had a few in recent weeks), your mpg will be lower in the colder weather.

Can you tell us any more about what chassis the rig is built on? Again, I think 12-14 might be optimistic, but I would think 9-12 could be within reason. So you getting about 8 isn't that far off.

But, rather than dwell on MPG....HOW DID YOU LIKE THE RIG!!! :-) I've seen some Dynamax's and they looked nice!

Whatever the MPG, Good Luck on your new RV!

~Rick

What you see, is what you get. The older Ford gas engines/transmission combos are not known for their exceptional fuel economy. Power, yes, but at a price. What size is it? V8 or V10?

I think the previous owner was puffing. Has the engine had a recent tuneup?

It would appear to be an E450 platform, and presumably has the V10 engine. 8-9 mpg, or maybe 10 on a good day, is about what I would expect. 12-14 mpg strikes me as highly optimistic, possibly achievable if you're driving on level ground at low highway speeds, say 40-45 mph--basically as slow as you can go with it staying in overdrive.

65k in a 24 C with V-10

14 downhill with a tail wind, 12 flat with tail wind, 8 uphill or into a good wind. Avg over 65k 10.5

should add that was at 65ish mph

Pado wrote:
I purchased a used 22 foot Dynamax Isata Sport 220. It has approximately 42,000 miles on it. The previous owner said that he got approximately 12-14 MPG. On our first trip, we averaged 8 MPG. Does anyone have a guesstimate of what mileage I should expect? I realize this varies with many factors but am looking for a general idea. We do not tow anything with it. It is 14,050 lb. VWR and 20,000 lb. GCWR.

Thank you.

This is an easy one to solve. Based on specs very likely a V10 E450. Either the owner flat out lied about mpg or just was really bad at math. Expect 8-10, slightly less if towing.

On an E350 and E450, There is one thing that can be easily checked, if you think your fuel economy tanked, or your power is reduced, especially if you recently had the radiator replaced.

Disconnect the oval air intake from the leading connection and pivot it upward. In the hole it was snapped into, inspect to make sure there is no obstructive plastic flap blocking the air flow. If there is, you have to lift that large plastic radiator shroud, fold the obstructive flap back, and set the shroud back down.

There was a recall some years ago where a line worker failed to fold the flap back, creating the obstruction which messed with power and fuel economy.

In getting a bird carcass out from our radiator, I removed the shroud and accidentally recreated the scenario. Fortunately I caught myself before I was finished.

In Pado's case, if he has the smaller V8 engine in an E350, he just might average 12 mpg because his motor home is so tiny and aerodynamic. But drop at least 1mpg with the larger V10 engine.

I just checked. I do have a V10. Thank you. I will be checking all suggestions.

Thank you all for your comments. I have not figured out how to reply to each of you individually so I am replying to everything here.

I am not sure when the last tune-up was performed. I have not had one done yet but plan to do it this week.

We traveled from Virginia to upstate NY in October. The temperature ranged from about 50 degrees to 70 degrees while driving.

The terrain did have it's share of hills!

We calculated the mileage 3 times. Each was calculated off of a full tank of gas.

Thank you for the tip about checking the flap on the radiator - I'll check today although engines are not my thing but I'm very into learning - I may have a few more questions once I get under the hood!

The chassis is a Ford E450. (22 feet) It is a Ford 6.8L, Triton V-10 engine (415 CID, 305 HP, 420 ft./lbs. of torque @ 3250 rpm.