 VW does not have any loyalty incentives  in place for the owners returning their TDIs. VWs answer when asked why not is the incentive to the TDI   customer is the added cash when you sell the car back (you get the cash if you repurchase a VW or not). I will take the money and not buy a VW again. If they have no loyalty to a TDI owmer why should the owner have loyalty to the VW brand.