2009 Yamaha Grizzly 450 Auto. 4x4 IRS, AUTOMATIC - THERE'S A LOT OF GRIZZLY IN THIS MID-SIZE PACKAGE. A mid-size ATV with our exclusive fully automatic Ultramatic transmission, On-Command two-wheel drive / four-wheel drive with differential lock, independent rear suspension, digital meter, rear sealed wet disc brake, two-inch receiver hitch and more.