[dradernh]

Originally Posted by SoftShoe

My ‘19 rwd lists 38-45 (front-rear) on the door. I’m running stock-sized non-run-flat Michelin 4S.

...is BMW recommending only for better mpg?

Or am I somehow destroying my car or tires as I make it much better (IMO) to drive by setting significantly (percentage-wise) lower-than-recommended pressures?

Also, the in-car monitor differs from my hand-held gauge by about 3 pounds. Is that normal? Yes, I’ll check with another gauge, but am curious if that’s a common condition.

1) Interesting, because my 2017 RWD shows 39 R & 35 F on the door sticker. It came with Michelin Pilot Super Sport tires, the predecessors to the 4S'.

While I've been too lazy to bother with changing from the OEM-suggested TPs, if I wanted to fully-exercise my car on public back roads I'd start with 34 psi front and rear.

2) It would seem so.

3) That's quite unlikely.

4) I don't even look at the in-car TPs. I use a very expensive digital gauge that I acquired when doing competitive events and the differences are significant.

I use a race shop for day-to-day maintenance work and asked them last week about TPMS read-outs. The shop owner said there's a +/- 3 psi variation in what the typical DOT-approved TPMS sensor reads out. IOW, they're not particularly useful unless you're a typical owner who expects the car to save him from himself. Welcome to modern "life"?