i have a 98 R/T i get 12mpg every once and a while i get 13mpg,so be papared to spend alot of time and the gas station. i have heard the is a 275/45/17 but dont quote me on that

 

i have a pretty much rebuilt engine, heads, headers, cam, injectors, rockers, rods, intake manifold, ect.. and i get avg 13-14mpg but i also have a Single Cab.. and right now i have 255/50/17s on the front and 275/55/17s on the back

if you want to use the truck for racing to get better hook ups, get some 285s they fit on the stock rim they are 17x9 i was also told you could fit 295s on them but never seen them on the rim only herd about it.. but i have 275s right now on the rear and they hook up DAMN well.. better then the 255s.. i have some yokohamas all around.

 

The window tag for an R/T says 12 city and 17 highway