alimo698

I just changed to snow and I checked the placard at the driver's door, it stated that the tires need 32/38 FR, but then when I check the fuel door, it said if under 160mph use 32/32, and over 160mph use 34/38 or something, and then add to the confusion, if u intended to load stuff in it, then switch back to 32/38....so why driver's door state 32/38? so confused....

So what are you guy running with? 32/32? as I don't think i will ever bring my 550 over 160mph......

thanks!

ezinternet

The tire pressure stickers on the car are specifications/suggestions for the stock / supplied wheel/tires. I say suggestions because you can still play with the pressures somewhat to fine tune the ride quality, as long as you don't under- or over-inflate and compromise tire longevity or safety.

I bought Pirelli Scorpion Ice&Snow 275/40 VR 20 tires for my ML63 for winter. These are MB suggested tires for the application, but nevertheless Tirerack suggests that these be run at 42 psi all around. I'm waiting for the car at the shop right now, so I can't yet say how they ride.

vinceching

i do 38 psi all around.

alimo698

I finally got some time to play with the air pressure, I tried 34/40, and found out that the rears are not using the full tread. As on flat ground, I drove it slowly like 5mph and roll it through some sand and dust, and only 80% of tread is being used, (actually almost half the outer most block is not being used) so I reduced it back to 34/34 and seems like 95% of it is used (almost right up to the shoulder block). This is when the tires are hot already. So i am sticking with 34/34 for now...

PDXman

I'm travelling so I dont have direct access to my car...
To add further confusion my car has 3 different recommended pressures: 1) one inside the door on the B pillar for what must be thew stock tires 2) a separate different suggested pressure in the same location for the optional 19 inch 50 series tires and 3) a final different pressure on the fuel door. Of course, when calling the MB dealer they suggested a 4th different pressure. Can you say confusing!