Howdy!! I need some recommendations....

[NotStock]

First off, hello!! I happened upon this site and its perfect for what I am about to build. I have been plannin a build of a fuel efficient motorhome/toyhauler that is capable of towing a 8k lb trailer. I first purchased a 1987 MCI tour bus, and just recently a 1995 Cummins 5.9L school bus. All to find that neither will fit my needs without MAJOR modification. I have someone interested in trading me an expeditor for the tour bus. The expeditor is a 1999 Freightliner FL70 (750k miles) with a new CAT 3126 engine, allison MD3060 auto tranny (6th gear is .65:1), spring suspension, with a rockwell rearend (5.29 ratio). The most important for me is fuel economy. I understand that a certain amount of hp/tq is necessary and less will actually result in lower fuel economy. Would this expeditor fit the needs well for a truck conversion capable of 70 mph crusing speed and get 10+ mpg? Thanks for your help guys and I will be here often!!

 

[BlizzND]

Welcome aboard, this site is fairly quiet, but I'm glad you found us.
I am building a similar project, hoping for 10plus mpg, my truck is a 2001 GMC 6500, with a 210 hp 3126 cat and a 6 spd man trans 3.07 rear gear with 19.5 low-pro tires runs down the road 80mph with ease, I don't know mpg though.

There is an expediter truckers website, they would know that truck design inside and out. might want to Google them.

Tell us more about your truck, gears? tire size? and engine hp. These trucks eat up a lot of hp (and the 3126 isn't a 500hp Turbo Caterpillar engine). When you build big tall boxes that catch wind expect to pay at the pump.

How far do you plan on traveling and what kind of 8000lbs are you towing? Some boats pull easier then enclosed car trailers and horse trailers. Again, wind drag means so much.

Are you building a new box or fitting out the expediter box? check out the photo section here, many nights of idea shopping there.

good luck, keep us informed, perhaps we can help each other out here.
-blizz

 

[BlizzND]

here is a link to my project,
blizzard's conversion
-blizz

 

[geofkaye]

....rear end is very low for 10mpg and with a big box.....I'm saying 6mpg-maybe 7 at best at 70mph. I have a 16k wrecker with a 3126 and a 6speed with a 3.92 rear......6-7 mpg with nothing on the deck and 5 mpg with a car up on her-another on the stinger I get maybe 5.....good luck with the fuel mileage issue-but I don't think it will happen.....I don't know what DOC WEAVER gets with his but you might ask...he's on this board with a red box truck with is pretty close to what your talking about.....geofkaye

 

[Doc Weaver]

I'm still trying to get an accurate MPG, but driving style has much to do with MPG. If I set the cruise at 65mph, I get phenomenal MPG. I drove from Cincinnati to Knoxville and back on little more than 35 gallons of fuel. That's over 14 MPG!!! I know, I know, I don't believe it either. This is why I need some more testing.

I had an Isuzu NPR that would get 9 MPG if I were alone on the highway. Conversely, the same truck would get 13 MPG when traveling 30 yards behind another truck. I learned to draft with that truck. I'd like to try Daytona next

Doc Weaver