Car feels wobbly after new tires

[Shakman]

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"?

I have the exact same symptoms when I replaced both my rear 19” tires. Now the car doesn’t like to go straight esp when decelerating. Autopilot feels like it’s goi g zigzag slightly to compensate. But it doesn’t feel like an alignment issue. It goes straight but if slight steering in either direction at hwy speeds doesn’t return it back to going straight again.

Did you find a solution? Can you share?

 

[derekt75]

I have the exact same symptoms when I replaced both my rear 19” tires. Now the car doesn’t like to go straight esp when decelerating. Autopilot feels like it’s goi g zigzag slightly to compensate. But it doesn’t feel like an alignment issue. It goes straight but if slight steering in either direction at hwy speeds doesn’t return it back to going straight again.

Did you find a solution? Can you share?

Honestly I don't remember 9 years ago, sorry.
I think the problem became a non-issue after driving more on the tires.

 

[The Duke]

I have the exact same symptoms when I replaced both my rear 19” tires. Now the car doesn’t like to go straight esp when decelerating. Autopilot feels like it’s goi g zigzag slightly to compensate. But it doesn’t feel like an alignment issue. It goes straight but if slight steering in either direction at hwy speeds doesn’t return it back to going straight again.

Did you find a solution? Can you share?

I had this on mine with second set of tires. Alignment needs to be at the minimum factory settings, almost exactly. If they aligned them "good enough" and in spec but closer to the max settings you get what you describe as well as rapid tire wear. Tell the alignment guy, minimum settings.

 

[NewbyMaybe]

Psi can also be an issue.