Running 40 PSI vs 35

Most of the time my FWD cars are empty in the back or have a few grocery bags, and drive in the city on rough roads.
I set the fronts to placard and rears 4 psi below. Always set on a cool morning.
If I load up the back or go on a road trip with suitcases I fill the rears to placard.
 
Run a chalk test to figure out your ideal PSI, and remember that those door jam and sidewalk numbers are COLD psi.

I get even wear at 36/32 psi front/back on my truck. The truck feels planted and secure without a lot of drag.

I’ll bump up the rears 4psi if I’ll be carrying heavy loads or towibg
 
Here’s what I’ve always done to get a baseline. set to factory pressure, cold. Drive it for a while. recheck pressure. If it’s more than 2 degrees up, add air. If it’s less than 2 degrees higher, lose a little air, as long as it’s not under factory spec. I usually found that the front in a typical fwd car would come up to the mid thirties, and the rear would be a couple pounds less.

did that for years and found that the car would start to feed back a sweet spot, especially noticed in balanced f-r feel when cornering. I’d fine tune it from there.
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