[Roma]

I usually check my tyre pressures at least weekly. I got gawjus back last week so checked them early this morning. The dealer had pumped them up to 35psi. I had to let out air from each tyre to bring it back to 31psi (19" wheels). I'm guessing the dealer is just assuming that the car will be driven above 100mph and adjusts the pressures for that sort of speed.

I recommend checking your tyre pressures after any visit to the dealer! Incorrect tyre pressures cause premature tyre wear, affect fuel economy and handling.

 

[penultimateblack]

I can't see a wear problem if the pressures are within the recommended 31 - 36 psi band. I might use a compromise 33 psi on my next trip to Germany where 120 mph is not unusual.

 

[pekem]

It would seem to me that by setting at 31psi the accurate calibration of the pressure guage and temperature would be critical; and rarely are guages so accurate that an indicated 31psi could be relied upon as being true.
Most manufacturers of the widely available digital guages, now regarded as the most reliable, mostly work to plus or minus of .05 psi over a range of 5 - 150 psi.
So I think it would be wise to aim for the middle ground of Jaguars recommendation.

 

[craig]

Why do they assume the higher limit? especially in the UK :roll:

 

[pekem]

Why do they assume the higher limit? especially in the UK :roll:

They might also have a faulty tyre pressure guage

 

[thegasman]

Mine were all set at 38psi. I've let them down to 32 and the ride feels more comfortable.
Why set them to the 100mph+ pressure when there are no roads you can legally do over 70mph anywhere in the country?

Martin

 

[pekem]

Mine were all set at 38psi. I've let them down to 32 and the ride feels more comfortable.
Why set them to the 100mph+ pressure when there are no roads you can legally do over 70mph anywhere in the country?

Martin

It would be of interest to know from the Service Manager if that was the pressure(38psi) they intended to set them at.
And if it was; why :?:

 

[davidfbird]

The tyre pressure "placard" was missing on my car, so for the first couple of months I just kept the same pressures as on delivery, i.e. 35 psi (seems to be a popular dealer figure, according to this thread). I rang the service department today and was told 31 psi. which I assume is correct for 17" rims. I wonder if 4 psi will make much of a difference to the ride?

 

[sodgob]

Thought i'd go middle of the road... 19" wheels & 34 psi

 

[penultimateblack]

Ditto - I'm using 33 psi with 18" wheels.