I just bought a 06 S-Type 4.2 with the 17" wheels. The dealer delivered the car with 43psi in all the tires. The car's label says to inflate to 32 psi, but, that seemed too low to me. I settled on 35psi, but, they still look a bit under-inflated. Can I run 38 in them without problems?? Appreciate your advice.

Regards:
Oldengineer

 

I amassuming that your tires are 235/50/ZR17. If so, sure, you can run 38 psi, but I bet they will be bouncy. I am running the recommended 32 psi in my 2005 S-Type 3.0 and I believe that is ideal. I may step up to 34 psi in an attempt to get a bit better treadlife and gas mileage, but I do not believe that I would go any higher than 35 psi.

Some tire brands handle higher pressures better than others. I have always found Bridgestone and Dunlop to be in this category.

Just my two cents. Experiment with your pressures and run whatseems best for you. I reallyquestion running a 50-series tire at 43 psi, though....

 

Hi,
I upped my tire pressure about 6 months ago to 42 psi all around to decrease rolling resistance and get better fuel economy. The ride is a bit harsher but not uncomfortable as the suspension is very well set-up and compliant. I've been averaging 27-28 mpg per tankful since doing this. I still have my original tires with 66K miles on them and haven't had any noticeable increase in tire wear since increasing the tire pressure. Hope this helps you.
Vic