Regardless of whether the #s that were printed in DP magazine are accurate or not, I am living proof of diesel over gas as I averaged 10 to 12 in my 2003 F350 V-10 and I am getting 17 to 19 in my 2006 F350 with the 6.0.

Both were/are 4x4 Crew Cabs with 3.73 LS and covers for the bed. So, I am getting a bare minimum of 50% improved mileage and in many cases, better than that. I drive both almost exactly the same. Light foot on take off and cruise set to 72. Most of my driving is highway....

Fish

 

I don't know where you are getting your milage. My F350 6.4, 600 miles, 4.30, dual, is getting 10.8 mpg highway at 70mph empty.

 

His mpg is better because he has the 3.73 rear end gear ratio. My 08' 350 DRW gets 17-19 mpg. I also have 3.73 gears. Normally the higher the ratio the lower your mileage. It's a trade off between fuel mileage and low end towing.

 

I went with the 4.30 to tow a 40' Alfa toyhouse. The 03 F350 6.0, 3.73,4X4,SWD I traded was getting 16 MPG at 35,000 miles. It just didn't do good pulling the 5th wheelup the mountian.

 

Sounds like a good choice with the terrain you're towing with the weight. I'm in the flatlands of South Texas so I didn't need the higher gears for the hills. Mine's working out great with 15K behind it.

 

I've got an '08 F-350 SRW 4x4 with the 6.4 and 3.73's. In town I am getting 10.4. On the Hwy with the cruise set at 62 I am getting right at 20mpg. This is with less than 500 miles on the rig so far. This is 2 lane as we don't have many 4 lanes here in Ak. EricL

 

Have you measured this manually or is this what the meter is telling you?

 

I have actually checked it both ways. It was within .5 of each other the first time and .4 the second time. EricL

 

That's great news to hear the meter is more or less accurate. I am averaging 14-15 mpg combined highway/city driving manually measured. I have never manually measured the highway portion only ( I have only 1,100 miles on) but the meter tells me I am getting 17-19 mpg on the hihgway so maybe that's fairly close.

 

test drove a 08 Kr F250 with 3.73 out to the house to see if would
fit in the garage. The computer said 9mpg. It fit so they located
a 250 that I wanted, its reading the same on the hwy 9mpg.
Hoping it gets betterl

 

Was it in city driving. If not that sounds too low. Mine never reads that low and didn't from mile 1. Dowes your truck also have the 3.73?

 

I read something in the manual about setting cruise control and resetting meter after 5 miles I believe to ensure more accurate calculation. Not certain here now )I am at my office) but it is in the manual. I'll try to locate and check later.If you didn't reset it is possible the wrong numbers are on your meter? 9 on highway is way too low IMO.

 

I have a 08 F350 LB FX4 4x4 6.4 PSD 3.73 rear and i have only gotten 10.5 average by computer and (13.5 average Figured by hand)at best empty driving moderate after 1100 miles on the truck.

The computer said 7.5 when i got mine from the dealership.

 

My calculated avearge was 14.4 but on the highway my meter was reading 17 to 20 different times. Your vehicle appears to be same as mine. I have the 18" wheels and the axle is limited slip.

 

Centex KR. The manual at page 124 lists the info about a minimum of 5 miles on cruise control and the need to re-set to get accurate highway fuel economy readings.