The oil question!

[prolfe]

By particulate filters you mean the Cat? I think all diesels have had cats since the mid 90s.

I've only serviced mine once since I got it. I used Mobil 1 as I had a small stock in the garage. For my next change, I might take a look at Millers - they have good rep.

Some of the models of VAG cars now come with a Diesel Particle Filter (DPF) but not all of the diesels. The higher performance ones.

[Dave Avant]

Some of the models of VAG cars now come with a Diesel Particle Filter (DPF) but not all of the diesels. The higher performance ones.

But what/where is this particle filter?

[prolfe]

But what/where is this particle filter?

Here is an abstract from the us patents office:

Diesel particle filters are applied in exhaust gas systems of diesel engines to retain the soot particles contained in the exhaust gas. The soot particles contained in the exhaust gas flow during operation of the diesel engine accumulate on the impaction-side of the diesel particle filter. In order to prevent the increase of counter pressure in the exhaust gas, the accumulated soot is removed by oxidation within the scope of a combustion process at regular time intervals or as a function of the exhaust gas counter pressure. In this way a diesel particle filter can be regenerated.

The dpf sits in the exhaust system and is the first thing the exhaust fumes pass through.

[Dave Avant]

So is not the same as the cat which on a diesel is called a particulate filter, that has been fitted to diesels for the past 10 years or so? Or is the DPF an addition to the diesel cat?

[prolfe]

So is not the same as the cat which on a diesel is called a particulate filter, that has been fitted to diesels for the past 10 years or so? Or is the DPF an addition to the diesel cat?

in addition

[Dave Avant]

Been reading up on this DPF.

Apparently it actually raises CO2 levels!! but reduces the soot particles which is more damaging to the human respiratory system.

Wonder how much it raises CO2 and whether it puts the tax up?

In my view all these so called emission devices, like cats and EGRs etc seem to work in theory, but they also produce other/or more damaging emissions. I think manufacturers should concentrated on getting the actual emissions down rather than masking it with add-ons.

[Marco34]

Been reading up on this DPF.

Apparently it actually raises CO2 levels!! but reduces the soot particles which is more damaging to the human respiratory system.

Wonder how much it raises CO2 and whether it puts the tax up?

In my view all these so called emission devices, like cats and EGRs etc seem to work in theory, but they also produce other/or more damaging emissions. I think manufacturers should concentrated on getting the actual emissions down rather than masking it with add-ons.

I agree with you there Dave Prolfe's description of this particulate filter was spot on. It confused me at first as to why you would need the 507.01 and what the difference is. All these different filters seem to try and cure one prob but kick out another noxious gas depending on what the 'experts' tell us is the least harmful. I'm all for minimising emissions but I'm sure these oil companies are on the band wagon to bleed more money out of fearing motorists. Use this oil else your engine will explode.. I've actually read that somewhere

[Marco34]

I'm with you Marco!!

I usually take the recomended interval and half it - so 5,000 miles based on a fixed service which is 10,000 miles. I've got about 1,000 miles to go yet. As I've been using my bike I've cut my annual mileage to about 6,000 miles a year. Done about 2,500 miles on my bike since May.

Glad to see others have the same thoughts on oils!

[Dave Avant]

Glad to see others have the same thoughts on oils!

Plus with my A4 being my first diesel and used to the oil staying golden in petrol engines, makes me want to change the oil even sooner with how black the oil gets so quickly.

On previous cars I tended to change the oil as soon as it went dark brown. When I sold my Rover coupe turbo with 96,000 miles which I changed the oil religously, had for 5 years and did 70,000 miles in - with trackdays, he didn't believe it had done the mileage recorded and thought I clocked it forwards!!

I even changed the box oil about 3 or 4 times - the box wasn't it's strongest point as it wasn't designed for 200bhp!! But it was still silky smooth as was the engine. Got a BMW 328 sport after that and the Rover engine and box were smoother and quieter esp. for a four-pot!!! Also didn't leak oil like many others.

I'm a strong believer in not having cheaper oils and not leaving it in too long as I think the acids etc that build up in the oil are not good for seals.

Yes oils are better nowadays at keeping in grade, but they still have to suspend and carry all the contaminants round that the engine puts in!!

I change the oil on the motorhome every year, so has had 5 changes so far, but only done just 20K miles!!