The most common complaint after front wheel alignment is the end position of the steering wheel this is a visual indication that
1: The workmanship was poor
2: The equipment is inadequate
3: Alignment was never the real problem
4: The manufactured cars axle is miss-aligned

Nearly every alignment test in the World is sold to the customer by the shop based on visual wear on the tyres at the end of there life, inevitable history of past alignment problems would still exist on the face of the tyre, born from this visible wear and potential loss of the new replacements a customer could assume a problem still exists and is easily sold.

Taking 1 to 4 here are my thoughts)-

1: No legal responsibility is required to ascertain the understanding of the technician who sets the direction of your £50.000 (theoretical) car with the new £500 front tyres, most common is a 'drive by' smattering of knowledge that involves undoing of nuts and about ten minutes additional time whilst you pay the bill, (so knowledge maybe why)

2: There are many machines on the market that promise different levels of alignment, most common is 'front wheel alignment' this form is the most damaging and by today's standard only suitable for the horse and cart, can i remind you that the car has 'Four Wheels', (so the equipment maybe why)

3: With the magnitude of problems expressed though the tyres during their life span it would be easy to assume alignment is to blame. Current issues with the Geometry or the cars health in general will cause untold affects toward the tyres and handling, this does not dismiss the fact that 'at the time' the alignment may be incorrect, (so maybe the car is why)

4: There are occasional manufacturing reasons that deceives the operator, this is unusual and depends on equipment, this is most times geometrically undetectable (so maybe the construction is why)

Taking all possibilities into consideration the common denominator is the 'Thrust Angle' the cars true centre at the rear,most angles depend on this as a reference......simple as that!

Any method that attempts to imagine the front wheels forward position relative the the fixed rear thrust angle will result in the need for the driver to compensate and manufacture a new centre line at the steering wheel, if any adjustments made do not respect the true 'Thrust Angle' then the resulting drive will mean the steering wheel is off-line.

Frightening....

Good read don't think I've ever had a good alignment done. And a few times returned with the steering wheel off centre.

Very interesting read there w.i

Need mine doing really quick as ive just had to replace a track rod end (MOT failiure). Ill have a read through the yellow pages and see whats what.

Jim

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Well no don't beat yourself up because of the industry's ignorance... Fact is if the alignment has no centre of reference then to adjustment is blind....

Next time anyone is in the tyre shop and they say you need wheel alignment can you please ask this question.

'What are you aligning the front wheels to?'..... If they can answer you i would be very surprised!

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The thrust angle is the key everything should be set to, not just the rears. Who says the rears are correct?

Also, especially with the state of the roads now, the angles can be out, even without banging up and down kerbs etc. General wear on suspension compnents over their life can also affect it.

I may not fully understand the entire theory behind how all the angles interact with each other (in particular can't get my head around how the kingpin inclination is changed when it is not directly adjustable) but I can say that the handling of my car (which I thought was good previously) was transformed after Wheels-InMotion did his magic on it - and this was after all the usual fast-fit and dealers had checked it all out using 4 wheel alignment equipment and saying nothing wrong (I was wearing inside edge so I knew there was something wrong)

Just had my free 2,000 miles tune-up today! Did I say that Tony is a great guy? We had a chat about wheels alignment, and about Internet forums  

Tony is also providing advice through the forum on the Wheels-Inmotion website, so if you are looking for more info check http://www.wheels-inmotion.co.uk/forum/.