Rear Tires Suddenly Lock Up Going 65
X2 on the don't drive it.
You want to fine but if you wreck it, oh well. Maybe if you keep the speed around 35 mph max OK but at 60 you could lose control and even kill somebody--if not yourself. Unlikely but a maybe, it happen once and it could do it again unless you find and correct the problem.
Losing control at speed is no fun what so ever. If I never feel that sinking lost control feeling again it be a good thing.
I would lift the rear up and rev it in gear and listen for any odd noises.
You gotta find the problem--and DON'T sell the darn thing saying it works fine. lol
It could last a long time before happening again but you never know and it could easily happen the next time on the highway.