W212 amazingly high tyre pressures

[Worcestershire]

Wow, new to the Merc scene, went to check tyre pressures so I could set the tyre pressure monitor thing.



I have the non sporty 17" 245/45 tyres, pulled into garage, checked the B pillar, not there, checked the fuel filler cap, there they are. I had to take a photo as I thought it must be wrong.

38psi unloaded, and up to 48 on the rear fully loaded, Jesus wept, is this right. I've never had a car above around 33/34

Is this what people run theirs at ?

 

[artyman]

I have 245/45 17's and run them at 32

 

[190]

I think the car manufacturers must be pushing pressures beyond what is needed to carry the weight purely to reduce rolling resistance and improve MPG.

The only way to find out for sure would be to find the load tables for your specific tyres. These tables are produced by the tyre manufacturers and list the weight each tyre can carry at different pressures.

 

[tonysmb]

I do run mine at the 'recommended' pressures but agree that they are higher than generally used to be the case.

I've notice on another car, different manufacturer, that they list different, ie higher by some 3psi, pressures for the 'eco' model. I did run that one, whichvwas the eco model, although I couldn't ascertain what other differences there were, if any, at the lower of the two stated pressures. I did his for 9 years and never had a problem with it. I ran them at 33 instead of 36.

 

[such01]

My tyre pressures, as recommended by the chart for my 19 in wheels - 39 psi front & back unloaded.
I ran the fronts, UR3's, at 34 resulting in uneven wear to the inner and outer edges down to legal limit with the rest at 4mm.
I now run the replacement GAS3's at 39.

 

[rf065]

I ran my 19" tyres at the recommended pressures, which are high, and they all are wearing out in the centres, so I'll be lowering them.