I've noticed this since I've been driving with the donut. Fortunately, it's coming off tomorrow.

The car's alignment was fine prior to putting the spare on, btw...


With the spare on the back left, the car is really tracks bad to the right. In fact, the steering wheel is actually left of center in order to keep the car straight down the road. If I put the wheel square, it goes off to the right.

Now part of the reason is the fact that the road is graded to the right, and the car has a tendency to follow the grade. But even on flat roads, I noticed this too.

So I checked the size of the donut, and it's a 155/80/17 which is basically the same overall rolling diameter of the 245/45/18 that normally sits on the back. So that can't be it.


But could it be that fact that the width of the spare is a 155 while the other 3 tires are 225s (front) and a 245 (back)? Could the much large contact area on the right side of the car versus the spare and a 225 on the left side be the culprit?

I gotta think that's it or I'm miffed to why it's pulling quite a bit.

Thoughts?

 

Absolutely it's the width of the tire.

 

Thanks Neil. I figured it was that.

 

I'm thinking it would be worse on the front for steering.

 

Definitely the spare, and its definitely worse when on the front wheel. Since the tire has such a narrow contact patch, the car actually does lean a little that way.