I have the stock tires on my 2008 HCH. I do not know much about PSI but I know the higher the PSI the better gas mileage. I don't want to put the max psi on the tires because im afraid of when it gets to 80 here it might expand to much and ruin the tires.

Any suggestions will be helpful. Thanks!!!

 

I keep mine both at 42 PSI. Everyone has their own opinion on how full they want their tires. By the time the temp rises 20-30F your tires will probably have lost some air. It is also a good idea to check your PSI every few weeks.

 

Same pressure all year for me... 50 PSI across all four tires, regardless of outside temp. Yes, for those of you watching at home, this is slightly above max sidewall.

 

I ran my last tires at 51PSI for the life of the tires. The Dunlop's were rotated every 15K miles, alignment every 20K and the tires lasted for 88,000 miles.

Not bad!

 

I'm in Michigan where in the summer it is usually in the 70-80's. What would you guys suggest as a PSI for that?

 

The same pressure, year round. Something above minimum cold tire pressure as indicated by your manual or the sticker in your door jamb or gas cap. Increase to compensate for load. Higher pressures with a lighter load means reduced traction. Don't sacrifice yours or anyone else's safety on the road to save a bit of fuel.