gearing and tires

I now have 4:10 gears running 275/70r/16 tires, wondering what the effect would be if i put the stock size on for the winter?

the effect will be higher rpms. dont know what stock tire size is for 16 rims, but i think you should be fine. just realize you will be geared low and your tranny will be shifting at a lower speed because the rpms will be higher than what your used to.