I bought a 2000 f-250 v10 with a 8 inch lift and 35 swamper boggers on it last month and i cant keep up with the fuel gauge,i can go about 50 to 60 miles on 10 gallons of fuel.It's got 61000 miles on it it was taken care of,yesterday my front brakes started makin a metal to metal sound so maybe that could be a part of the problem slightly rubbing brakes etc.But either than that can u guys gimme some suggestions on what to look at or if u think i should have a dealer run a diagnostics?

 

Well lets see.....V10.....8 inch lift.....45 swamp boggers.......your milage seems just about right with all that. Pull the wheels off and see if you can turn the rotor by hand. If so then no rubbing. I would check the brakes anyway with 61K..The lift sure does not help the brakes!!!!!

sounds like you got what you got. i get about 250 - 300 miles ot of 30 gallons with no lift.....and a free flowing exhaust.

 

Not what i was hoping to hear,but if it changes your opinion there only 35'' swampers.If i was to change tires to try and improve MPG what suggestions would u gimme on brands,i still wanna mud the truck everyone once and awhile and they'd have to still be 35"s

 

Were the axles regeared when the lift and tires were put on? What ratio is in the axles? How wide are the Swampers? Right off the bat it is obvious that the tires have something to do with it, but 5-6mpg is pretty bad, even with the mods.

 

Howdy Swampa,
What are your gears?? Go to www.4Wheelparts.com and look at their gear chart. It tells you which gears go with which tire size for best economy or towing......... A gear change will help but it will still be less than stock.

 

45's were a typo.......35's I meant

 

That is some bad gas mileage if your speedo wasn't calibrated for those 35's your speedo/odometer will read very much slower than than should so when you figure your mileage it will be lower
I went with 315's and i get about 400 miles a tank (38 gal tank) with mixed driving

 

8 inch lift has you creating MUCH more areo drag UNDER the already poor areo designed truck. I would almost bet that the front alignment is set too much toe in or out and that will eat mpgs bad too.

Swamper Boggers in any size are the very worst rolling resistance tire designed and not for highway driving, they are designed for off road.

2000 V10 most likely has 3.73:1 rear gears so there you are at under 2000rpm in OD (well below good HP and Torque rpm band) with your tall truck and dragging big heavy cool looking tires getting a whopping 6 mpg... sounds right about what it should be getting to me. My old 460 lifted with GIANT mudder tires barely got 7mpg down hill with Strong tail wind..

Welcome to the costs of looking cool. I take back the nasty tone if your intent is to spend most of the time mudding... then you will appreciate the abilities of those tires. But in town, on the highway? Nope, they suck more than fuel, they are heavy, they steer like rocks, and they are very loud above 40mph.

 

Its a good point about the speedo being calibrated. Assuming all is well there, Id go with a tire that is as tall, but narrower than a bogger, and more suited to street driving, but still maintains a rugged look, BFG AT or something like that. Assuming it is driven on the street frequently.
I had a 94 F350 with a 7.3 (not powerstroke) lifted 9" with some 41" Michelins on it, and a VERY heavy set of rims. Tire and wheel combo weighed 250 lbs a piece. Yea yea, its a diesel, but it saw much better mileage with those tires then with a wider set of 42" swampers. Width makes a big difference in mileage. Just for reference, I was gettin around 16mpg unloaded at 65. I know its a diesel, but it should still give you some idea. Id expect you to see around 10-12 with a better set of tires.