What's the best way to maintain a DPF?

I own a 2007 Volvo XC90 with 118k on the clock. Lovely motor and mostly trouble free but it's recently started missing the odd beat and intermittently going into limp-mode. The other day, when in limp-mode, I tried to accelerate hard, to no avail, and got the message "soot filter full". My local garage says that it can sell me a DPF cleaning fluid or that they can do it for £140 warranted for 12 months. Is this a good idea or should I replace it with a new one? I do a lot of my own maintenance work but I am not overly familiar witth DPF "best practice" so to speak. Any advice would be greatly appreciated.
We would assume that you have been doing quite a bit of town driving which can the lead to the DPF not actually regenerating (i.e. burning off the soot on the DPF). At this stage we would suggest that you take the car onto a motorway or dual carriageway and drive the engine revs at 2000rpm for at least 25 mins .

This should then activate the regen process and clear the soot (dependent on how blocked the DPF is). If it does work then (and if you continue to do town type driving) then you may need to do the motorway run every three months.
Answered by Alan Ross on

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