police package

I have an 08 Impala Police that I'm wanting to change the wheels on, it comes with 16" steel wheels, but the 12-13 Police Package came with 17" steel wheels and hubcaps that look much better to me (and also have a smaller tire sidewall). There don't seem to be many listings online but I'm just...

The speedometer in my 2009 Impala Police package sometimes starts jumping at red lights. Only happens when the car is at a stop in Drive. If I start moving or shift to anything other than Drive it stops. The tachometer stays steady. Occasionally when it happens it'll jump all the way to the max...