I got new tires on my car about a month ago. The max tire pressure listed on the side of the tire is 51lbs. I check them earlier today and there arounf 33-34 all the way around. The car is garage kept in upstate ny. It been chilly, but not bad. So, did they all lose 16-17 lbs in 5 weeks or did the dealer underfill them? A few PSI seems reasonable, but 16+?