Agreed on the minor change in psi.

Studies show that before tpms the majority of tires were under inflated more than 5psi though there is a chance some accidents were causes from it, the legislation that brought about TPMS requirement was based mostly on saving gas.

People that track their cars will adjust up and down for what they need and it is likely not related at all to the door jamb guidance.

It probably takes at least 6-8 psi drop to be a significant issue for handling, wear, temperature damage.

Most people will not noticed a difference in handling before 5psi change and 3-4 psi drop is not going to cause enough a problem with emergency handling.

Example math;
My car with 1200# and 33 psi 1200/33=36.364 in.² contact patch.

Drop that psi to 29 : 1200/29=41.379 in.².

5 in.² difference would likely be enough to be difference in snow not too likely to be a problem otherwise.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)