Im replacing my tires soon and cant decide if I should go with 33's again, or go a little smaller.I have 3.55 axle gears and the automatic.If i go an inch smaller will that achieve better fuel economy or hurt it.I do mostly city driving with a bunch of hills.any advice would be great.

 

city driving it might help just a lil. highway milge it will hurt just a lil

 

your not gonna notice a difference from 33's to 31's if you were going from 40's do 31's there is a huge difference. go with waht makes the truck look good and your happy with. performance difference will be unnoticable

 

Id say keep the 33's as well. You wont be able to tell with that small of a change!

 

I run 33" on my D250 and wouldn't dream of going smaller. I could even handle a taller gear like 3.31/3.21/3.08 because this is my DD, so I'm usually in a hurry, and want to save fuel on the longer drives.

 

I went from the 245/75/16s that came on it to 33s and my mileage stayed exactly the same at 17.5 and I noticed no power loss towing.