When I had my ’98 Explorer, I kept my Class III trailer hitch attached to the vehicle. It was a good thing I did, as I was rear-ended several times during the time I owned it, and that rear hitch took the brunt of the hit, thus never damaging my vehicle.
Now there’s a rear trailer hitch designed specifically for such impacts, in that it compresses to some degree when hit. This portable spare bumper protects your vehicle from rear end collision damage caused by tailgaters, uninsured motorists, bumper-to-bumper traffic, distracted drivers, inattentive cell phone users, drivers with poor judgment, text messengers and lousy parallel parkers… Another advantage is that it also acts as a step in order to help you reach your roof rack.