Can anybody interpret an Alignment check report for me ?

[beedj]

Just got my Audi Q7 back from dealer. I had taken it in after noticing that the nearside front tyre was bald at outside edge (c.9000 miles from new).

They rang me earlier to say they have performed a four wheel alignment but that the adjustments they made were not material, and hence wouldn't explain the wear. They are saying that therefore there was no alignment problem and the tyre wear is normal.

However ... they have left a copy of the alignment report in the car, showing a "Before" and "After" graphic. In the "Before" graphic the wheel in question is highlighted red (with a positive number), whereas the others are all green. In the "After" graphic everything is green (now with a negative number for the wheel in question).

I'm no expert but this suggests to me that something was wrong, and the adjustment was more 'material' than they suggested.

Grateful if there is anybody able to properly interpret the report for me and give me their opinion ...

[cptsideways]

Does it say camber?

[driverrob]

Excessive negative camber or toe-in will produce the wear you describe. A decent wheel alignment print-out will show the limits (for your car) for these two plus castor and the current values, red if outside the limit, green if within them. They don't normally change of their own accord so it looks as if the steering geometry has been wrong for some time.

[HRG]

Can you scan it and post it up?

As has been said, going from a positive to a negative value means something was out of kilter

[beedj]

[driverrob]

That's not hugely out, David.
Some years ago my rears were many times further out than that and it took a track day and 6,000 miles to wear out the tyre edges.
Could the tyre have been under-inflated, too?

[Incorrigible]

Very slightly out, combined with slight tyre underinflation and a tendency for you to hoon round roundabouts perhaps

I didn't realise they ran such large castor