My DPF died a couple of months ago, strangley enough not long after a service! Anyway, I have a Toyota Used Car Warranty and so was able to get a new one after the Toyota Garage explained to the warranty person that a DPF is not actually a consumable filter but a DPNR! It costs over £2K! BTW Lexus said it was NOT covered under their warranty due to it being a revised DPNR (08).
I have since found out that cars equipped with DPF MUST used low ash oil and so you must check this next time you get your car serviced. Ash is not combustable and so will block your DPF.
If I keep the car and it happens again, I will
1. Undo the hoses and clear them and the ports
2. Connect the hoses together so that the Pressure Differential Sensor is not telling the ECU it's blocked
3. Run at high revs. Although this didn't work last time and it's scary when you suddenly lose power. (passive regeneration)
4. If all else fails, I will take it off and blast it with a Pressure washer until it flows freely again
I am NOT paying £2k for a new one! Modern diesels! - New block, new DPF, dodgy DMF! Not been impressed!