"Kinda squirrely" sounds like low tire pressure or a tire that is too wide (and thus allows more movement).

When I was a kid, we always pumped our tires up and gave them the "feel" test. This assumes you're inflating to 40-50 psi or so. If that tire's supposed to be inflated to 80 or 100, he may still be inflating them to 40 psi.