New federal rules are forcing auto makers to include a “roll over” rating on sport utility vehicles. Radio Iowa talked with someone involved in an S-U-V roll-over.Mike Ralston lives in Nevada and commutes to Des Moines every day, so he puts alot of miles on his vehicle. Two years ago, Ralston was driving his Ford Explorer on a crowded Interstate in a torrential downpour. Ralston’s S-U-V was forced off the road, and it rolled over in the median.Ralston was wearing his seatbelt. Federal officials say your chances of surviving an S-U-V roll-over go up 75 percent if you’re wearing a lap belt and shoulder harness. Did the wreck spook Ralston about S-U-Vs? He says it didn’t and still feels they’re a safe vehicle. Ralston’s still driving a Ford Explorer — but it’s a newer model. S-U-Vs have a higher center of gravity, making roll-overs more common.