The 275/45/21 are too big, go with the 275/40R21's
If you want comfort stay away from 21's.
hi...The Michelin Latitude Tour HP are the smoothest, quietest and softest tires for this Ml350.... read this > https://mbworld.org/forums/new-m-class-w166/543311-softest- most-comfortable-quiet-tire-ml.html
My 04 E320 Temp gauge went blank while driving and the car will only go up to 60 mph the speedo is stuck on 60 mph and very sluggish. My coolant was low and the cap was very loose. The next day I service the coolant bottle try to start and it will not turn over all I get is a clicking sound from the left front of the engine.
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