[rondeo]

The DPF is a filter which traps soot. By googling I see that about 200 grams of soot might be collected in the DPF per 1000km. This amount is more than the system cope with and has to be 'burned off' periodically by "active regeneration' at 600 deg C, done automatically and more or less transparently by injecting diesel fuel into the exhaust system prior to the dpf. So one problem might be constant short trips, where regeneration fails because things aren't hot enough. . . Ford, tell us more...