Gunson 'Trakrite' wheel track gauge

In message , Cicero writes

The garage that I buy my tyres from have used them for about 15 years. They swear by them and I've never had any problems when they have used it to do the tracking on my cars.

I have one, in my opinion they're great. It seems pretty accurate and it's easy to use as long as you have somewhere totally flat to use it :)

Tony Bond ("Tony Bond" ) gurgled happily, sounding much like they were saying:

Does it do anything you can't easily do with two pieces of straight wood, a ruler and a biro...?

Yes, it measures your tracking when the wheels/suspension are loaded up and the car is moving forwards (albeit slowly). It's results are also more repeatable than setting it with pieces of wood and string (at least in my experience, I used to use that method before I bought the gauge).

No, because these days none of them are any good. I've got a '60s-'70s Dunlop caliper gauge, but I haven't used it in ages. I always have mine done on a laser bench (Pro-tyre in Bristol)

It'll set toe-in no problem (caliper or Trakrite). What it won't do though is to set the toe-in up accurately centred on the chassis. You can set it all up crabwise and you'll never know.

If you have toe-in to adjust on the rear too, then you've got particular problems. It's all too easy to set the front up crabbing one way and the back end crabbing the other. Now if you've fixed tracking at the back and only the front is crabbed, then you might pick it up by road-testing (hands off on a flat runway). If each end compensates for the other though, it's impossible to detect just by driving it - but the handling is still impaired and you're scrubbing at your tyres.

A Trakrite is the cost of about 4 tracking checks on a laser bench, or two check-and-adjusts. Unless you're kerbing the thing every week, that's a lot of mileage.