My tire pressures were WAY off when I got the car - the car felt Awful until I read something here about high delivery tire pressures - so I watch them a bit. I noticed that they (all 4 together) went down from 37 to 32, then 30, then 27 - and still no warning light. I had the car serviced and they said that the TPMS system was fine - it triggered at 25 psi, just like it was supposed to.

HUH? My BMW would trigger at about 3 psi. I can't believe that one tire could drop 11 pounds below the others - and who knows what the high pressure limit is - and no warning. Maybe there's a test for pressure and one for differences - IDK.

I blame some of the change to weather, but can't believe all of it is because of that. Has anyone else had problems keeping air in?

And, as expected, when the pressures dropped, the ride became more plush and the steering response less sharp. 32 psi felt pretty good to me, but I don't canyon-carve much - live in a huge city.

 

I don't feel that I've ever had to add air other than to address seasonal temperature changes. I tend to run a bit higher (38psi) as it doesn't feel harsh to me, and it feels a bit firmer which I like.

My TPMS has never ever triggered. My 2014 doesn't display pressures, only warnings. Allegedly. Someday, I'll drop the pressure on one tire to see if it responds.

 

Some cars measure the actual pressure of each tie, others compare the rolling circumference of each tire to the others.

Two different method, but neither has an over pressure setting.

 

Presumably, the method of comparing the rotational rates of each wheel should show if one is overpressure, if it leads to the rotational rate difference being high enough. Doubt it's smart enough to figure over/under pressure.

The F-type has a TPMS sensor on each wheel.