Hi, I have a 2007 Jaguar XKR, owned from new and the front tyres are suffering from very poor wear. The original tyres and all replacements have been Dunlop SP Sport Maxx J (255/35 R20 Y).

after 73,838 miles, it is now on its 4th set of front tyres and they look as though they need replacing again after only 9118 miles due to heavy wear on the outside edge, were it is smooth on the near side and has only slightly more grip on the offside.

The tyre wear seems to be getting worse as the car ages.
Front:
Original tyres lasted 27,768 miles with no uneven wear.
2nd set lasted 23,032 miles and were very worn on the inside edge of both
3rd set lasted only 13,920 miles and were changed in March this year. They were also very worn on the inside edge with 5mm on the rest of the tyre.
4th set are still on the car, but after only 9,118 miles they are wearing badly on the outside edge (the opposite of the last set)! The tread is thicker on the inside and slowly reduces to nothing on the outside edge of the near side tyre. The offside is only slightly better!

Rear:
Original tyres lasted 21,340 miles.
2nd set lasted 19,780 miles, with the offside being more worn than the nearside.
3rd set lasted 18,883 miles and were both worn in the centre (possibly due to over inflation!).
4th set are wearing evenly after 13,885 miles and still have plenty of grip.

In March this year, after changing the tyres that were worn badly on the inside edge, the tracking was checked but found to be okay and so wasn't adjusted!

In the early years of owning this car I found that the rear tyres usually had more wear than the fronts, which is understandable on a rear wheel drive, but now this trend has reversed.

I would really appreciate some advice about why the fronts are wearing so quickly as given the extortionate cost of tyres these days they are costing me a fortune.

 

Wow,

I'll start, by saying that if the wear is repeatable on all sets you have, then it is time to
a.) alter your tire choice or
b.) alter your tire pressures
c.) step away from factory alignment specs
(This assumes you have no worn components)

As I have never run the Dunlop, I'll leave others "in the know" to talk about them.

Tire pressure is specific to each brand and design, so if you living off the "generic" figures posted on the door plate, you might think about getting a pyrometer and setting the pressures more accurately.

If you are consistently wearing the outside edge then you might dial the camber a little more to the negative side. Keep in mind that tire shops have an "acceptable range? where they will call you alignment good. Request they hit the mark at the most negative setting, or go to a performance shop willing to step outside factory specs.

BOL
Vince

 

Unfortunately there doesn't appear to be any consistency, other than my front tyres are consistently wearing out much faster than they used to, which is why I'm struggling to understand why this is happening.

Previous front tyres both wore out on the inside edge, these tyres have worn out on the outside edge, and much faster. I always maintain the same documented tyre pressures 2.1 bar front and 2.3 bar rear.

I'm currently over-inflating the fronts to 2.3 bar in the hope it may wear the centre of the tyre more and avoid the outside edge, but they still need replacing.

 

Your tracking may be OK but that tells you nothing about the camber and caster. I suspect you have a bushing (or bushings) going out somewhere in the front suspension. Maybe there is a means of adjustment for the camber or caster that has shifted. Only a jag dealer or a suspension specialist can check that out for you.