I suppose this isn't "Jaguar specific" however, I am curious to know what you guys run your tyres at, and what kind of wear you get out of them?

I currently have a set of Pirelli P6 225/60 ZR16 All season tyres, per the owners manual I currently have them inflated to 28 PSI all the way around (book suggests 26PSI in the front and 28PSI in the rear). My main concern is that it is for maximum comfort, does this effect fuel economy much? Also, the rear tyres are every so slightly weather checked, and I do a lot of high way travel at speeds of 55mph-80mph, my worry is with such low pressure on weather checked tyres should I be concerned about a blowout?

And before anyone suggests that I replace them, there is about 40% tread left, give or take, and I wont have the money to replace the tyres for a while. Unless 100% necessary.

Thanks in advance!

 

Since English or even US-English is not my native language I don't know what you mean by "weather checked".

28 PSI seems a bit low to me, I prefer to run my tires around the 35-37 PSI-mark. To start with I would go to 32 PSI and see how the car handles.

At 28 PSI I don't think there is any risk of blowing a tire.

 

Tires heat up extremely while hard cornering, and on hard braking.
There is no reason to be afraid for a blow-out at the highway speeds you mentioned due to temperature, as they will be relative low at such conditions.

Having said that, Jaguar is advising rather low pressures.
I presume they do so from a comfort point of view.

I ran the same tire sizes as you before, and found the F32-R34psi work perfect from a comfort point of view.
They were wearing more from alignment-issues then from pressure settings.

 

+1 32F, 34R. Higher pressure hardly effects the ride but is much safer at highway speeds.

 

30 PSI all around.

 

The correct tyre pressures for the XJ8 under most conditions is 32psi front
and 34 psi rear.
For extended high speed use, up the pressures to 34 front and 36 rear
These by the way are Jaguar specific figures mentioned in their hand books ;o)

 

Then you forget to mention that the same hand book mentions F26 and R28, calling it maximum comfort (<160km/hr; 100 ml/hr) .
These pressures are IMO rather low.

 

higher pressure reduces tire contact (and resistance) and increases mileage.
the maximum comfort of 28/26 will reduce gas mileage. In my case, up and down hills, this pressure will also wear out the inner and outer most part of my tires before the center of my tread would wear.
Look for wear patterns at the lower pressure. Also, reset the mileage computer at each gas fill up and compare that to tire pressure. The difference may not be significant.

if a tire is under inflated, the sidewall will flex more when the tire rotates to the bottom. Flexing causes heat. Heat increases pressure.
Tires will run at an equilibrium of heat/pressure.
An under inflated tire will run HOTTER than a properly inflated tire.

 

As per those above, and the handbook, somewhere between 28psi and 35psi according to personal preference. I run my Pirelli P7s at 35psi and find them quiet and comfortable.

.

 

The OE PZero System tires have reinforced sidewalls allowing for the lower pressure ... my dealer parts guy (very knowledgable) told me the exact tire is NLA .two years ago .... although Tire Rack has them again and lists them as OE?

There are many tires in the PZero line.