+1 to the above. Use the oil specified in the owner's manual, and use whatever brand of diesel you have a loyalty card / money-off voucher for.
If the car gets a run on open roads for a distance of more than 10 - 15 miles or so a couple of times per month, that will be enough for the DPF to regenerate.
There's no need to thrash the engine, or give the car an 'Italian tune up' as is often suggested -- these just create more soot. The DPF system is designed to work under normal driving conditions.
|