Originally Posted by shadowglenn
Wow I thought this would have had the typical all across the board range of answers. I am thinking about trying 30 psi for now. I would try the "Chalk Test" but I feel it would not work very good on the currently snow covered streets.
Bigger tires take less pressure; 38 PSI is way too high for a 33" aftermarket tire. That's probably why you feel em hopping. The one tire that's 32 is closest...that's what I'd try first. Go with 32, drive it, and if it's still a little squirrely go down to 30 PSI.
As a rough guide, 33" tires will need about 30-32 PSI; 35" tires around 28-30, etc.
If you've got a really thin layer of snow, you can do a rough kind of chalk test with that, by seeing how much of your tire coverage shows up...