I had the same thing happen to my 70 chevy truck in 75 after having new tires put on at Sears. left front wheel came off. i worked there at the time and took it in first thing in the morning on a work day and they the could work on it between of jobs and someone forgot to tighten the lug nuts. i drove it on the highway at 70mph to look at a new house then back home and to work the next day, wheel came off 2 miles from home at a stop light. heard a grinding noise then the truck went up to the right and when i looked out the wheel was laying in the middle of the intersection.
