It depends on what size your snowflakes are. They come in a few sizes. You probably have at least 15x6, which should be fine for 31x9.5's. You can also check what the manufacturer recomend as the minimum rim width for that tire. It's usually included with the rest of the tire specs somewhere like tirerack.com.
Snowflakes came with 31x10.50 tires, and they fit just fine. Many have run 32x11.50s on them as well. Mark runs 33x12.50, but that's too wide in my opinion on a 7" rim. 33x10.50 fits fine however.
A forum community dedicated to Isuzu SUV owners and enthusiasts. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, and more!