The biggest failure mode of the early gearboxes was the internal clutch damper.
The clutch damper guides getting destroyed by the springs and the resultant debris getting pumped around the gearbox and blocking the internal filter (starving the oil pump).
The later design has a proper external Dual Mass Flywheel, no plastic fantastic bits to get mashed up inside. The rest of the gearbox is fundamentally the same, you can drive the later geabox with an early Mechatronic unit (and some work).
The gearboxes are completely different bikt patterns, early mate to the Euro5 engines and later gearboxes matr to the Euro6 engines.
My thread has a few pictures of each gearbox.
The later boxes are not infallible BUT the main failure point has been removed.
Wife rang me up at work saying the car was playing up (Mk2 Kuga Powershift). Got home and managed to get it to fault again. Managed to pull code P0766, shift solenoid D stuck. First port of call is to flush the box, only did the oil change 15,000 miles ago though with genuine Ford oil +...
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