Ok, before everyone decides to dogpile on the newbie, here is the reason behind my posting. I am looking to order a 2011 F250 with the PowerStroke. I am replacing both my daily commuter and my fun truck (Dodge Dakota 318 4x4) with the new F250 since my family and the weight of my toys have grown beyond the size of the Dakota. 90% of the miles I put on the truck will be unloaded highway commuting to and from work so fuel economy has some value to me. I have looked at serveral of the posts on rolling radius of the tires and the knock-on fuel economy effect of the 3.31 rear end. Thus my assumption is that bigger tires and lower axle ratio would yield the best mileage, but this runs counter to the advice I have recieved from the dealer. This group seems to be deep subject matter experts so I thought I would put the question out here to see what your thoughts are. Thanks in advance for the help.

 

DOG PILE! What's wrong with you newbie? Don't you read the forums before posting?!?

Just kidding...

Welcome to FTE. Lot's a great guys and gals with great info here.

Not sure why your dealer would disagree with your logic. Of course the lower rear-end and factory tires are going to yield the best mileage. The 6.7L engine is so powerful that if you ever need to tow anything moderately heavy, you'll be just fine. There are others on here with good engineering backgrounds and can explain why, but I think you've already come to the right conclusion.

 

Thanks - sometimes salemen and logic don't mix.