S60 - rack changed now steering vague

Hi

Had my rack changed just before Christmas. It was badly worn and that had
really knocked out the tracking, so I neeeded two new tyres too. I put two
new F1s on the back, and swapped back to front. It now feels, well, "weird".
Very vague straight ahead, and some wander on white lines.

The tracking was supposedly done when the rack was fitted , but trusting
no-one, I had it rechecked elsewhere - result, spot-on and no adjustment
needed.

Now, I have swapped backs to fronts before, and I know that this wasn't
always advised, but this (I thought) was now preferred. Don't recall any
sympoms like this previously, though.

Any views on whether this is a tyre issue, or whether there may be another
fault? I appreciate that I need to take it back to the place where the rack
was changed, but as I can't do that until next week, any views or opinions
would be useful.

Thanks

Tim

 

Could be tire wear or tire pressure I suppose.

However, the S60 is not that old a car that steering rack wear would
be enough knock the front end alignment out. Was the car in an
accident? I suspect that there may be other damage involved here.