If it's an ML350 Bluetec, it will be a 2010 model, so really "late model." You'll have warranty for 4-years from in-service date and up to 50K miles, so any "issues" won't be too costly.

There really aren't many issues left with these models, as they've been around since '07, but there are some "features," such as whether you like the brake pedal feel and can live with a bit of clunkiness apparently inherent in the interface between the diesel and 7-sp transmission.

These vehicles come with HR-rated tires which means the car is electronically limited to 130 mph (which it will do) and this means the car is fitted with "performance" tires that, if you're lucky, will last for 25K miles. Many folks that don't understand Mercedes seem disappointed by this.

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Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles