I have an 05' F250 Crew Cab 4wd w/ the FX4 package (has V10 motor) with about 53k miles on it. The prior (and original) owner replaced the OEM BF Goodrich tires on it for Firestones! The Firestones are about shot and must go. Current tire size on it is 285/75 R 17 (stock wheels) and I just kind of assumed he replaced the tires with stock size. Well the door panel says 265/75 R 17 is standard. Which is right??

If 265's are the standard size, will I see any noticeable improvements in power/accelaration going back to a smaller diameter tire? My truck is an Auto w/ the 4.10 gears.

BTW, I'm pretty dead set on Michelin LTX tires as I've had great luck with them in the past. However, I'll listen to suggestions! Truck sees little off road use, but Colorado winter roads often. About 85% on pavement highway or town driving.

 

Yes, the 265/70/17 were correct factory size. They are about 31 inches tall and the 285/75 are about 33 inches tall. I'm not sure if you would notice a difference but your speedo might be more accurate with original tires, if it was not recal'd. Just make sure the new tires you get are Load Range E. This is a debate (D or E) I suggest range E.

 

Thanks 07! Yep, Load Range E without a doubt.

 

Mine came with 265/70/17E Pirelli Scorpions as stock, not BFGs, not that it makes a difference I guess.

 

You should use 10 ply tires. It's awfully heavy, and if you combine that with a load the tires won't be able to hold up to it without the added reinforcement.