All it takes to roll any vehicle is enough momentum and a ditch or
culvert. You probably drive past 100 situations on your way to work
that could cause a rollover.
There is a nice video of a guy driving a TR on the track when his axle breaks.
Also, a good roll bar stiffens the rear section of the passenger
compartment and add a little side impact resistance.
When that Hummer H2 rear ends you and climbs up the slope of the
trunk, you'll be glad the roll bar is there to form a safety cage of
sorts not only over your head, but behind you as well.
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