I have a 3 1/2yr old Nissan Qashqai (25K miles) which has suffered the known knocking problem on and off since new, first experienced at 6K miles. 1st set was replaced under Manufacturers warranty and the second set failed within 6K miles of fitting.

The Nissan dealer did not fit the revised standard dampers so when the knocking sound returned (warn bushes by the way) they had to replace at their cost.

The car was exported to Switzerland in March 2010 and has only covered 5K miles in the last 14 months. The knocking has returned again and the current dealer (Swiss) states that the lower mod standard had been fitted again. My advice is to push your dealer to confirm which Modification standard will be fitted and push for FOC replacements.