The Nitto Tire website shows the approved rim width between 10" and 12"
with a 11" rim being the recommended width on the rear for a 305/35/18, and a 9" to 11" with a 9.5" rim being the recommended width on the front for a 275/35/18.
I'm running a 18"X9" front with 245/40/18 Nitto 555E and
18"x10" rear with 285/40/18 Nitto 555E.