I purchased 4 new tires for my 2005 Cadillac STS some months ago. Their are two different tire sizes that are required i.e different sizes for front and rear. At the time I also purchased the road hazard package which includes rotation, balance, etc. in addition to lifetime alignment. Every 5k miles I brought the vehicle in for an oil change with the instruction to check the alignment; never assuming that I also had to instruct the technician to balance the tires. After approx. 20k miles on the new tires I began to hear significant road... read full review »