Should an alignment be done any time you get new tires on the Z?

I had Nissan do a 4 wheel alignment about a week ago for the tire feathering TSB. A few days later, I got new OEM rear tires but did not get another alignment since I just got one.

My rear end is now kind of nervous. For instance, the rear will jump a little to one side or the other after letting off from moderately hard acceleration. Never loses traction though. Lane changes feel a lot different too. Almost too much enthusiasm from the rear.

Anyways, my theory is that old tires turn into cones (inner diameter smaller than out diameter) due to the negative camber wear. If you have an alignment on old tires and then get new tires then the alignment will be thrown off. Is this correct?

Thanks,
Jeff

 

You are correct. If they aligned the car with worn tires then the alignment would be off with new tires. They should have waited for the new tires. Good luck getting them to realign it.

The twitch your experiencing doesn't sound like an alignment problem though. I'm no expert.

 

I had my wheels aligned a week after getting RH J5's I also installed Tanabe GF210 springs which dropped the car about 1.2 inches all around I went to the best place in town (allegedly) and I asked the guy if I need to align everytime I change rims or wheels, he said not neccessarily it's when you mess with the height of the car that you defenitley need to get an alignment.
In any case I don't think it's a bad idea to get the wheels aligned whenever there is a change.
Goodluck

 

I would say when you get new rims, get an alignment. New tires shouldn't matter. They align based on how the wheel sits, not how the tire sits. Or at least that is what they did when they aligned mine.