I think Ford names all their engines Duratorque. The 1,6 tdci and the 2,0 tdci and 2,2 litre tdci are all engines that comes from the PSA group. Ford maybe add some minor tweaks to the engines, but the base is from PSA.
Only the 1,8 tdci is a original Ford engine as far as i know.
PSA & ford do quite a bit of sharing in the engine dept... it also includes the 1.4tdci found in the fiesta, 206 & bmw mini - in addition to the above!
The deal ford did with psa meant that ford would supply the v6 tdci found in the bigger c/d cars as psa didnt have a decent engine to use...
ford do the 2.0, 2.2 & 2.4 i4 16v engines found in land rover, jaguar x-type and transit et.al. + the 1.8 8v - all of these engines are built at the dagenham diesel center.
the 1.8 is the longest production running ford diesel - it originally started life as a petrol engine way back when 950, 1.1, 1.3 & 1.6l were all the rage (known as the kent engine)... its under gone many engineering changes over time to keep up with emission regulations - but its still a good engine - now diesel!
ford produce the psa 1.4, and soon the 1.6, at dagenham for the ford range rather than obtain the engines pre built from psa...