Strange tyre (tire) wear. JGC 2.7 CRD 2002.
I'm getting some weird tire (US)/tyre (UK) wear on my Jeep. When I bought it 2 years ago I noticed that the N/S (left) front tire was badly worn on it's outer (left) edge. I insisted on new front tyres before purchase and that the track should be checked. This was duly done. I know the track had been altered as clean thread was visible on the trackrod.
After 15 months and about 4000 miles the L/H front was more worn on the L/H edge than over the rest of the tire. I had a specialist tire fitter swap the tires from left to right and vice versa, maintaining the same direction of rotation, and re-check and adjust the track. After another 2000 miles the now L/H (formerly R/H) tire is showing signs of the same symptoms.
The Jeep has just been in for service and the wheel alignment, track, camber and castor all checked with laser gear and found to be O.K.
My experience tells me that usual causes of this problem are :-
(a) Excessive toe-in, which one would expect to affect both front tyres.
(b) Grossly excessive positive camber on the affected wheel or
(c) Negative castor, which which would cause the outer edge to 'scrub' when turning.
Assuming that the service engineers know what they are doing, and all the above are as per the manufacturers specifications, what the hell is happening?
As the 2002 WJ is beam axled at the front I wouldn't have expected camber or castor to be adjustable.
The only thing I can think is that the LSD (limit slip diff) in the front axle, if indeed it has an LSD, is not permitting the L/H wheel to rotate at the correct speed when cornering causing a 'fore and aft' scrub, rather than a sideways one. When I was stock car racing the cheaper alternative to an LSD, and stopping wheelspin, was to weld up the planet gears in the diff. This used to have some weird effects on tire wear when racing on tarmac!
Has anybody experienced similar, and do you have a solution. I don't like tires becoming illegal at the rate mine are!