SW17LS

Dealers ALWAYS over-inflate the tires. No need to take it back, just deflate them.

Lexzam

As said already above:

lower tire pressure equals worse fuel economy and used to mean early wearing out of the edges. However, the latter is not really so much an issue any more with new tires.

higher tire pressure is better for fuel economy, heavy load and fast driving. Conversely high pressure used to wear out the middle early on, but not any more an issue with today's tires. One can safely exceed the recommended tire pressure quite a bit. The ride should also be harsher, but the difference is much less than low profile tires compared with standard profile tires

SW17LS

Theres nothing about modern tires that makes it so under-inflation won't cause excess wear...ins a matter of physics.

praetor

I concur. Not to mention that under inflating your tires can cause excessive heat buildup. Heat alone will shorten the life of your tires. Run flats especially have the heat problem and that's why you can only drive it a short distance if you lose tire pressure.