The recommended tyre pressures for my 2010 Mazda 6 is 32 psi all round at all speeds, but I have always kept them a little higher at 34 psi. Now, the tyres have spent a bit more time on the front are showing wear on the inner and outer edges of each tyre, which indicates under inflation. Advisors from two major tyre companies have advised me that 32 psi is heavily biased towards passenger comfort and to increase pressures to 36 psi. What do you suggest when the carmaker and tyre company recommend significantly different pressures?
The tyre guys are correct that carmakers set their pressures based on a blend of performance, economy, comfort and wear. Tyre companies generally advise that you run higher tyre pressures for better performance and economy, but that will compromise the ride comfort. I would run a higher pressure for the benefits to handling and fuel consumption. Make sure you rotate your tyres regularly, that will even out the wear over the life of the tyres.