onetwopunch

Bfg at's all the way. I'm running them, love the looks and they last longer than any tire i've ever ran.

HOHN

55mph is going to give you almost as good a mileage as your rig is capable of.

Want to find the speed of maximum mpg for your truck? Put the truck in the highest gear you have and slow down to a speed where your boost gauge registers no boost (assuming stock turbo) on level ground. Then do a "lug test" by gradually acclerating. If your truck can pull away without lugging, you're near the speed of best mpg.

Some interesting mpg figures from my HO 24v: (take with grain of salt, as this was varying weather conditions)

52mph: 25.4 mpg (6th gear, almost lugging at 1500rpm)
60mph: ~23mpg
68mph:~ 21mpg
72mph: 20 even (almost always, regardless of condition)
75mph: 20 even, to high 19s.
83mph: 15.5mpg (low tire pressure in cold weather--bad headwind, too)

Needless to say, I try to keep it under 75. I typically run 72 on the freeway, whether it's posted 65, 70, or 75.


If a person is willing to putz along at 55mph, my truck delivers remarkable mpg.

Justin

1BAD4X4

Well, I was more so meaning since the 315s... before with the 265s I got just about the same milage from 55-70... but if I do 70 now I have a 3 or 4 mpg difference from going 55 mph... and it hits almost instantly, this isn't a gradual drop in mpg. But again I have a heavy right foot and when getting on the freeway I don't mess around. So that prob has a lot to do with it.

dansdodgediesel

At least the BFG's are Round. You'll get a better ride out of the BFG's.
Not to many tire's companys try to make round Tire's like Michelin does.