i am trying to find out what kind of milage people are getting on gasoline operated 7.0L in f-700's . my truck is propane , and mileage is terrrible so trying to decide if it may get better mileage if converted to gasoline carburator

 

you might be good at 7 MPG ! What type of truck , flatbed , box , dump ! what all is the truck hauling around , and how much does it weigh ? does it have a auto or manual tranny and the gears in the rear , any idea about the ratio ? our old F700 with a 429 got around 4 MPG it was a old gas company service truck with all tool boxes on it and a built in air compressor , we added 1000 gal tank to it for water and water pumps for drilling , it was geared low for around town use , top speed seemed like 55 mph , slow !

 

Truck is 1995 F-700 with manual trans 9 ft. dump body. i have not loaded this truck yet. this one is running off of propane impco 425 { I THINK }... I really want to convert it to run gasoline, cant find any info on doing this. all info i find is how to convert to propane.

 

me personally would rather have propane ! do you know if the truck came from the factory set up on propane ? i am going to guess that the gas tank is not on the truck , and it is fuel injected so is the throttle body there or did they replace it for the propane ? and do you know if all of the gas fuel lines were striped off the truck ?

any pictures would be nice if possible !

 

Truck came from factory with propane, was owned by home propane delivery co. for first ten years until 2005 , then it was stolen . this is a theft recovery truck. only 84,xxx miles. No fuel tanks lines or pump. could i put carb. on it ? Not sure if these things have really high compression, as that would affect its performance on pump gas

 

in your other post ,
thats around 4 mpg ? probably not out of line !

 

can i expect this mileage to get worse with 8 ton of rock on the back ?

 

you may be able to switch intakes with a carbed intake and then put a carb on it !
or build a adapter for were the propane carb bolts to the manifold !

 

would it be that simple ? no distributer change or anything like that ? i assume there is a plate on engine somewhere for a fuel pump , or maybe an electric one. thanks so much

 

all your electronics would stay the same just your fuel delivery method changes , i dont know how your emissions are up there and that could become a problem ! an electric fuel pump would work with the carb just get a low pressure one !

 

Thanks CJ. we dont have any type of emmisions here . going to try to figure if i can use an adapter plate with current intake. 2 or 4 barrrel going to get the best mileage?

 

that would depend on the opening in the intake , if big enough for a 4bl then i would use one if it is small than what a 4bl looks like then i would use a 2bl !

 

sounds nice . thanks

 

They get awful mileage!

I just finally sold the one I had.

I was very un impressed with the power to fuel consumption.

 

I've got an F600 w/a 7.0L gas engine. I have a horse van (box) sitting on the chassis, so, that makes it a horse van. The vehicle, a '94, is fairly new to me so I've only taken it on two trips with an 1100lb horse on it. The box probably weighs about 6000lbs with my truck weighing 6700lbs. First trip, I got 7.5 mpg and second trip, one where we got stuck in rush hour traffic and had a few more hills in the mix, I got 6 mpg.

Pretty damn good, according to a friend of mine who has a Hummer H2 and only gets 8 mpg when he tows his fishing boat with it.