D5 (2005 on) Longer runs but more DPF regenerations - underlying issue?

[skyship007]

Originally Posted by nikk530d

When you read the net, you can only find that more motorways driving results with longer regeneration intervals and vice versa. When I was reading Proghound's posts I felt like reading my own words.
So, everything is exactly the same, even the distance we cover every day (20 miles). The only difference is the car (my is Bmw 530d 2007). I also checked my car with diagnostic software with no faults appearing. It's interesting that the backpressure is always very low, even when the regen process starts. But it seems everything is fine then, the car just takes the advantage of my driving style.

Diesels with a DPF are bad news if you short trip or get stuck in traffic a lot. Stop-start ones are better as regards inner city use, although in the long term they will all need a new DPF if you clock up some serious engine on hours.
The only things you can do to reduce DPF fouling is to use a top quality fuel additive like LM Diesel purge when replacing the fuel filter to keep the injectors clean AND Liqui Moly Ceratec (Contains both Moly and Boron nitride) oil additive to reduce the wear of the valve guides and rings after about 100K km (Post full break in). With a high time diesel a top quality stop leak might be needed if the valve guide oil seals start to fail.
If you keep the oil consumption low with the correct use of various cleaners and anti wear additives, it will stop ash forming in the DPF which is the ultimate killer.
In a bad case try Mobil 1 10w60 EP, as it will resist the effects of diesel in the oil and has some good seal conditioners, plus anti wear additives.

The long OCI's (Oil change interval) quoted for modern diesels are nuts unless you only do long fast motorway trips. 5 to 6K miles max before changing oil BUT there is no need to change the oil filter until the normal recoomended limit (Dirty oil filters are far more efficient than clean ones).

[nikk530d]

Thank You for the helpful advices! I am already using a fuel additive called Monzol 5c, it's well known in Germany where you can buy it. I still haven't tried with oil additives, but before the next change I could try with LM Engine Flush and LM Ceratec.
Btw, what is you driving style and how frequent are your regenerations?

[Proghound]

To Nikk530D -

Sorry I missed your posts yesterday. To answer your question, I'm still doing the same routes every week and it's still working the same way I described, and there have been no failures in the DPF or the pressure sensors.

The regeneration cycle that I was previously used to changed, when the sort of mileage I was doing changed, it's as simple as that. I've got used to it this way now. If anything, I now find it unusual if it goes over 400 miles without a regeneration - it made 850 miles once, and that one took ages to complete!

[nikk530d]

And your regen. interval is now between 200-300 miles or more variable?l

[Proghound]

Originally Posted by nikk530d

And your regen. interval is now between 200-300 miles or more variable?l

Yes, it's mostly 200-300 miles but sometimes goes longer.

[nikk530d]

Yesterday I had a regeneration after cca 200 miles. It took only 7 minutes to complete and the backpressure dropped to only 1.8 mbar at idling (the max. permissible value is 35 mbar). According to this, I conclude that my dpf is very clean and contains negligible amount of ash. Is this right?