Assuming the crossmember with spare tire doesn't bounce over the Toyota!!!!!
I was behind a Ford F-250 Diesel yesterday going through a constuction zone. He was about 5 cars in front of me and when he hit the new pavement bump his spare let loose. A bunch of sparks appeared first, then, his spare grabbed tread and "uprighted" itself under his bed (~50mph). Next thing I knew the tire was 30 feet in the air and cleared the first car behind him, then took course for the right shoulder and finally the bushes.....scary!!!!