Is the gear shift knob in a 2000 Alero replaceable?

Yes, the gear shift knob in a 2000 Pontiac Alero is replaceable. It's generally a fairly straightforward process, often involving unscrewing the old knob and screwing on the new one. However, the exact method might vary slightly depending on whether it's a push-on or screw-on type. You might need a small tool to help with removal, depending on the design.