If you want to sell for other reasons, then that's another story.
But you are probably in for a rude surprise if you are downsizing just to save fuel.
Your current rig has room galore, which of course you have become used to. Selling will mean a big hit on depreciation, and there is no guarantee that you will do much better than 2 mpg better in claimed fuel economy.
The salesmen don't "know", because they probably don't want to hear.
The larger Class C's will probably be on the Ford E450 chassis, which is not known to be especially frugal.
My neighbor drives a 24 ft Class C, Chev 8.1 and gets 9 mpg on level ground.
I drive a 24ft Class C, Ford 460 and get 7 mpg, though I did a lot of travelling through the rockies.
We both tow a small car (Toyota Corolla). Both vehicles are stock. No $$$ spent on extra performance or emissions equipment which might or might not be legal in your jurisdiction. Our results seem consistent with other RV friends we know.
VicK's numbers don't agree with my experience, even if he is using the old Imperial gallon rather than the US (160 oz vs 128 oz) for the conversion.
Bottom line: trading just for the fuel economy reason doesn't make sense to me.
If, as you say, you are travelling less in the future, then keeping your current rig might be the better solution.
* This post was
edited 03/18/08 07:05pm by buchrob *
'99 Glendale Royal Expedition 24' Class C
2003 Subaru WRX wagon as toad.
I have a '94 22ft C on a Ford chassis with the 460 EFI. Have done the 3" exhaust line, removed the cat converter, Banks Air Flow, K/N air filter. Run reg fuel. On cruise at 55 mph I get 13.5 mpg on the flats with no side/head winds. I don't tow, run full of grub, water, kayak, wine, bourbon, 2 adults.
I have a 2001 Minnie 31C with one slide-out on a E450 W/6.8L V10. Towing a Jeep Liberty on a trailer, approx 6000 lbs. Last 17,243 miles MPG comes out to 7.8 MPG. Almost all Interstate travel with cruise at 63 MPH.
2001 Winnebago Minni - 31C
Ford E450 - V10 Triton
Tow - 2005 Jeep Liberty
Vic K from Canada wrote >>>> I have a 2000,28ft C on a E450 chassis and I get approx. 13-14 MPG on reg pump gas. I do not tow anything so those that do most likely would not get that much. I did replace my stock air cleaner with a K&N as soon as I got it home, and it seems to have made a difference in my motorhome. I take it over the mountains from Alberta into B.C so my route is always the same and my milage stays between 13-14 MPG. All I can say is to try to make the engine breath easier and do the speed limit and you should get reasonable MPG's.
garyhaupt from Canada wrote >>>> I have a '94 22ft C on a Ford chassis with the 460 EFI. Have done the 3" exhaust line, removed the cat converter, Banks Air Flow, K/N air filter. Run reg fuel. On cruise at 55 mph I get 13.5 mpg on the flats with no side/head winds. I don't tow, run full of grub, water, kayak, wine, bourbon, 2 adults.
My reply is what do you folks up there in Canada have in your fuel,, because I have not seen or heard of any fuel MPG results like this in Class C RV's,, mine gets 8-10 mpg and most post are at low of 6 mpg and high of 11 mpg..
Can you send me some of that fuel I could use a lot...
I get 8-10 mpg. Towed my minivan from San Diego to Pittsburgh and back last year on a dolly and mileage seemed about the same, maybe less than 1 mpg different some times.
2000 Four Winds Five Thousand 28A (Chevy 3500), Master Tow Dolly, 2000 Chevy Venture minivan TOAD
We always laugh when people ask us this question. We tell them we can get almost 10 mpg going downhill with a tail wind. Really thought we get about 8 with our tow dolly attached.
Tracy and T
Jayco 2001 Class C 3150J Designer
"The Girls" Honey and Crystal our dachshunds
Just read the Go-RVing newsletter, and they have a great spin on the mileage question....we can carry more people in our RVs, so we get more PMPG (People Miles Per Gallon)
With that philosophy, I can't help but add that if we have a toad that gets 30-35 mpg, and we tow it, we're "saving 30-35 mpg!!" Tree huggers have to like us for that!!
Regarding the trade in an A for a C to save some money. I have to agree with on of the previous posters, you're going to give up more than you save....all things being equal. It seems that the only way you'll save real money with an RV, is to go with a "B", or one of the diesel Sprinter chassis models, and then you are giving up A LOT of room, and diesel is more expensive than gas right now, so you may find that it's almost a wash.
My DW complains that we're paying $3 (and now more!) every 7-10 miles down the road I told her that we're paying $1-1.50 every 7-10 miles in her Honda van......she didn't think of that. I explained that we could get one of those little 2-seaters that Mercedes just came out with (40+mpg), but we give up sooooo much in room....no place for the kids, dogs, etc. With the RV, we're taking our kitchen, our bedroom, and our bathroom.......$0.40/mile almost seems like a deal
What ever you chose....enjoy it, and look at the whole picture!
Bill, Claudia, and the Paps
DH Bill / DW Claudia / DD Jenn / DS Chris The Paps! Sophie, Abby, Brandy, Kahlie and Annie
2000 Winnebago "Minnie" 31C, Ford V-10
Purchased April Fools Day, 2008 The Pets
garyhaupt wrote: I have a '94 22ft C on a Ford chassis with the 460 EFI. Have done the 3" exhaust line, removed the cat converter, Banks Air Flow, K/N air filter. Run reg fuel. On cruise at 55 mph I get 13.5 mpg on the flats with no side/head winds. I don't tow, run full of grub, water, kayak, wine, bourbon, 2 adults.
Gary Haupt
Gary I have the exact same setup as you(mines a 96 Jayco 22ft) with the same mods and the best I can do is 11.4mpg and thats at 55 mph. Is there anything else you've done to help it out? Plus I'm fairly light, no hitch, no water in water heater, no extra junk. I usually have 3 people. Do you have a generator and lots of goodies ?
Retired Anesthetist. Pilot with mechanic/inspection ratings.1996 Jayco C 22 foot with 460/Banks Powerpak/Bilsteins.Wife and daughter. Two cats which control my life. 1975 Ford F-250, 84 Coupe Deville, Thorp T18, tons of tools and tons of junk.
The little Mercedes treasures you are referring to no longer loudly shout about MPG in advertising. They may also be marginal in power towing a toad. And they burn that ever-costly diesel.
The calculations done by a few folks up north are certainly not subscibed to by me. Imperial gallon = 160 oz. US gallon = 128 oz.
That kind of ratio spoils all calculations.
If you go to the trouble of reading all the posts, you realize that you can expect 7-9 mpg. unless running downhill all the time.
Have a 2006 E450, Jayco Class C, 6.8L V10, not towing, weighing 12000 LB loaded, drive 65 MPH and am thrilled to see 9 MPG. Average is probably 8.5 MPG.
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I told her that we're paying $1-1.50 every 7-10 miles in her Honda van......she didn't think of that. I explained that we could get one of those little 2-seaters that Mercedes just came out with (40+mpg), but we give up sooooo much in room....no place for the kids, dogs, etc. With the RV, we're taking our kitchen, our bedroom, and our bathroom
.......$0.40/mile almost seems like a deal 
