Is it advisable to have my tyres below the recommended PSI?

I've just taken the plunge and bought 4 Michelin Cross Climates for my 2011 Mercedes E250 CDI Estate.Tyre size is 225/55 R16 99W. Mercedes Benz recommends 38PSI all round unladen, more when 5 up with luggage. I see that you regularly suggest running at lower pressures would you recommend the same for me and, if so, how is it likely to affect tyre wear as Mercedes suggested pressures would indicate I'd be running expensive tyres under-inflated?

Asked on 3 May 2017 by Lee1477

Answered by Honest John
I ran 215/55 R17s at 31PSI cold pressures all round in a Honda HR-V. Excellent comfort. Low noise. Good steering feel. No adverse effects of economy or wear. Probably not as low as that in the heavier E250 CDI, but cold pressures of 35 all round should be okay. As soon as they heat up they'll be 38 anyway.
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