25 years ago when I was at the bus garage, we installed stainless bushings in the school bus spring shackles. The kit replaced the soft metal bush with a stainless sleeve which had a spiral wound bushing like a close coil spring inside, plus a hardened shackle or eye pin.The kit reduced bushing replacement in the **** buses from once a year to just about never replacing them again.We also tried a bigger version in the king pins that worked out great.By the way ,on the IHC busses ,the stock bushings lasted 3 times those of the FORDS or GM full size buses.Stock soft metal king pins on older working PU's last about 50k miles if you grease them regularly. Loose king pin bushes cause the axle and spindle eyes to get egg shaped from the pounding of the loose pin.If you check the spindle eye of an old truck, most are worn egg shaped.Might be a problem with a Torrington needle bearing being forced out of shape when pressed in.A brass bush is more tolerant of dirt also.But if the suspension is in good shape, I bet the kit will improve the steering .
