Well, after 22 years of running polyurethane bearings, one caused trouble in the
rear. Iron oxide is to blame, as it takes more volume than iron. The passenger-side toe
arm broke. Fortunately, I wasn't going very fast and was able to get to safety in a
parking lot and call a tow truck. The problem had been there a while, based on the look of
the break. I checked all of the arms, removing all the polyurethane pieces and de-rusting
all the eyes. I also replaced the adjustment bolts and regreased everything with silicone
grease.
Turns out, I used the stock tube for lateral link #2. I wish I hadn't, as
it's not stainless steel. So, I made a new 316L stainless steel tube and polyurethane
bearing.