The service center just replaced my rear tires (21" Continental Extreme Contact DWs) My car now feels unsettled, like it wants to go in any direction other than straight. It's not the shaking of a badly balanced tire: there's no discernible periodicity to the wandering. Higher speeds feel more unstable than lower speeds, but the wobble is present at all speeds. It's unsettled when not accelerating. (It's more unsettled when stomping the go pedal, but that's not really new.) The tire was replaced after my wife had a flat tire. She said she didn't hit anything, there was no reason for the flat, and she pulled over as soon as the tire sensor came on. I've never known my wife to lie to me. The tire was completely flat. Some possibilities that I've thought of: 1) something hasn't quite settled. wait a week and hope it goes away 2) the service center didn't tighten something properly 3) the service center messed up on the install (including bad balance?) 4) the rim is goofed up -the cause of the flat could have goofed up the rim -the result of the flat could have goofed up the rim -the service center could have goofed up the rim 5) the alignment is bad -the cause of the flat could have goofed up the alignment Any thoughts? Do we know if the service centers do "road force balancing"?