Info on tires

Check the manufacture recommendations on the specific tire you want to run. You can find the recommned, minimum and maximum wheel width for tires on tirerack.

As I recall, you can run a 275 on a 10.5" wheel. The tire will look streched out to fit on the 10.5" wheel since the natural width is around 9". It will also leave your rims exposed to curb rash, but yeah, you should be able to run a 275.