Strange alignment problem

[jefword]

Hi,

I have just swapped my front wheels with the rear ones because the front tyres were down to about 4mm of tread and the rears were a cheap brand which I wanted to wear out before I put some decent ones on. (Front wheel drive S60 T5)

The strange problem is that my steering wheel is now slightly off centre when driving in a straight line, say about 10 degrees.

It was spot on before I swapped the wheels over and I do my own tracking with the old type Gunsons gauges and I'm particular about getting it spot on.

Just wondered if anyone had experienced this before or has any ideas as to how this could happen before I track it again.

Thanks in advance for any info.

[garagewidow]

get someone to drive behind you to see if the vehicle is tracking straight and not crabbing(though i can't see why changing wheels would cause this)
are the tyres worn evenly across their width?

[jefword]

Hi,
Thanks for your reply.

I must admit that one of the tyres I have put on the nearside rear is a little more worn on it's outside edge.

I don't think these tyres have rotation arrows (they just have "outside face" on them) so I could try swapping left with right to see if the steering wheel is out of centre but in the other direction.

[TheEnd]

Is it pulling to the left by any chance?

[jefword]

It does not pull to the left if I let go of the wheel on a flat road (it would on a camber though) but if I put the steering wheel in the straight ahead position it would steer left.

[jefword]

I have now swapped the rear tyres nearside for offside but the steering wheel is still out of centre & in the same direction.

[TheEnd]

I suppose take it in for tracking.
Maybe there was something wrong with it before, but hidden, or by coincidence, it's had a knock.

[jefword]

Hi,

Thanks for your reply.

I will track it myself and see if it's moved.

It had just been in for an MOT test. It was ok before the test and I didn't notice anything wrong on the way home.

It was then that I changed the fronts for the rears because of a tyre wear advisory. That's when I got the problem.

I suppose I could have knocked it on the way home but I do crawl over speed humps and avoid them if possible. Quite a few pot holes where I live but I don't think I hit any.

[TheEnd]

The most likely cause (discounting tyre tread and tramlining) is that one wheel will be knocked off centre a little, which would be driver's side with excessive toe in, and the auto self centring means you need to turn the wheel to compensate, and the, for example, 5 degree toe in on the driver's side becomes shared at 2.5 degrees both sides.

That should mean you should have roughly double whatever angle the steering wheel would cause on a single wheel, so hopefully it'll be nice and clear on the tracking gauges.