OEM 20”. 9/9.5 I think. 235/255/275RF? Staggered. I’m not where I can check.

The 34psi is TP in pounds per inch.

Thanks man.
Just think 34psi is a bit low for a 20 inch wheel. I usually go quite a bit higher. 50psi for the original 20" "AMG LINE" wheels, and the same for the 21" aftermarket wheels..

Probably does'nt make much of a difference.. However I'd prefer 50psi anytime (for theese wheels)

Mercedes recommends 35 lol

The recommendation varies, here's the sticker inside the fuel filler cap on mine:


Converting kPa to psi is roughly to divide by 7, or for bar throw a decimal place in after the first digit.

It depends on wheel size, load and temperature. That's why some are saying 35 (correct), some saying 40 (also correct). The highest according to this sticker is 50 (5 people on board and some luggage and heat in the tires).

I'm currently running on the 245/45/R19 W rated winter tires. Winters are legally required in Germany. The summers are the staggered 245/40/R20 + 275/35/R20.I only picked the car up (new to me) last week with a new service - I'm not even sure what they set the pressures to. I'll check what the TPMS display shows later.

At 50 psi, S or not, I would chip a tooth. Lots of variable factors dictate TP and there’s no shortage of experts. I have “street” rear tires that range from 275/20 to 365/19, Some run over 200 mph in their sleep. None have needed a TP over 40 on a track.

As to wheels, I’m not familiar a wheel dictating TP and at 50psi, I would be concerned with accelerated tire wear. You might want to watch the center tread section of your tires.

Did a Merc salesman tell you to run 50psi?