Pigeon-toed Prius rear wheels cured with strips cut from tin can.

We bought our fine '05 Prius in '09, and it came complete with slight hail damage and 125,000 miles. What I didn't realize was the rear wheels were toed in 3/8" ! I should have realized there was a problem after experiencing short tire life and cupping wear on the rear tires in spite of frequent rotation of the tires.. After wearing out two sets of tires I had the wheels aligned professionally. Before that I had only aligned the front wheels myself. Who would have ever guessed that the solid rear axle was sprung ? ! The man who did the alignment merely told me that there was a problem with the rear wheels. It was up to me to implement a cure. I calculated that a .007" shim in the front of each of the rear wheel spindle mounts was all that was needed. Sure enough, after installing the tin-can shims, I immediately felt a difference in how the car handled. Previously it always sort of wandered a bit, but after correcting the rear wheel toe-in, the car immediately went up the road like it was on rail-road tracks. Probably it is not a good idea to tie a rope to the center of the Prius rear axle to tow a riding lawn mower out of a ditch ! I remembered that some fifty years earlier my brother had experienced a similar problem with the rear wheels of a new 1959 automobile. He had driven over an unmarked bump in the road which was so severe that the weight and momentum of the differential had sprung the rear axle which caused the rear wheels to toe out. That caused cupping wear of the tires. Insurance covered the replacement of that sprung rear axle and solved the problem.