The Diesel Conundrum

[Billggski]

Apparently the main issue with electric cars is the panic that sets in when the power gets to 50%.
Power points are so far apart that the owners never venture far from home.

[taz777]

I've very recently bought my diesel S80 (3 months ago). I do very little mileage, but go for a long drive once a week. I love the car, particularly the effortless overtaking ability on fast roads. £30 per year road tax and very good fuel economy is a nice bonus, but those were not primary reasons I bought it. A slight downside is the clatter of the diesel engine.

The DPF issues are totally overblown. If all diesels had DPF issues then there wouldn't be any diesels on the roads.

Car forums will skew the perception of DPF-equipped cars as only owners with issues will talk about DPFs. For every owner that has a DPF issue, there'll be hundreds or thousands or owners who have no issues.

On my particular car, I've only senses the DPF regen once in my ownership. It took a long time (more than 30 minutes if I recall correctly) of motorway driving before the regen was done.

[skyship007]

Originally Posted by taz777

I've very recently bought my diesel S80 (3 months ago). I do very little mileage, but go for a long drive once a week. I love the car, particularly the effortless overtaking ability on fast roads. £30 per year road tax and very good fuel economy is a nice bonus, but those were not primary reasons I bought it. A slight downside is the clatter of the diesel engine.

The DPF issues are totally overblown. If all diesels had DPF issues then there wouldn't be any diesels on the roads.

Car forums will skew the perception of DPF-equipped cars as only owners with issues will talk about DPFs. For every owner that has a DPF issue, there'll be hundreds or thousands or owners who have no issues.

On my particular car, I've only senses the DPF regen once in my ownership. It took a long time (more than 30 minutes if I recall correctly) of motorway driving before the regen was done.

If you short trip a lot and don't do at least one good motorway trip a month, a DPF is going to be bad news. Replacing them is very common, even before the warranty expires.

Modern diesels tend to clatter more if you either use too thin an oil, or fail to change it often enough.
OEM spec is often an 0 or 5w30, when using an 0 or 5w40 German standard (Group 4 Synthoil), or GTL (Gas To Liquids) base oil will result in less noise when warm.
If the clatter is only during a cold start, make sure to use a real Volvo oil filter, as the integral relief valve might have failed or be set for the wrong oil pressure.

It's a good move to send a used oil sample off to an oil lab (I use Blackstone Lab in the US) to see if the oil is contaminated or has sheared out of spec. That way you can figure out when to change the oil. The limiting factor with DPF diesels is often fuel contamination or low viscosity. You can smell diesel from the dip stick when it reaches about 5%, BUT 2% is the normal limit for changing the oil. 2% results in a drop in viscosity of about 1 SAE group, so many folks that use 30 grades are in fact driving around with a 20 grade, when design spec for nearly all non hybrid diesels is an Xw40!

[Oil Burner]

Hi all,

Some really good discussion points being raised in this thread.

But to my original concerns/fears.

Yes my S60 (2005) has plenty of life left in it (hopefully). I was just looking at my options for a newer car before more things go wrong.

Yes I know it is cheaper to fix the odd problem each year for a few hundred pounds at a time over paying out 10-14k for a approved used car.

My concern with diesel in particular was in buying a Volvo Selekt used car of 2-3 years old that has just come out of lease and not knowing if the car has never been out of a ten mile radius of its home address and within a few months be plagued with DPF regen issues etc.

I would be more comfortable maybe with a higher mileage car out of lease that has done some serious miles to keep the DPF clear. But then again if reading on the internet is true, DPF's need physically changing after about 75k miles as they are past their service life.

This point is also linked to my original post whereupon I believe many owners will be offloading their cars as they near this mileage as they do not wish to pay for a new DPF and the new 'unsuspecting' fool who buys it has to pay for a large repair cost in possibly their first year of ownership.

[SwissXC90]

Originally Posted by taz777

Car forums will skew the perception of DPF-equipped cars as only owners with issues will talk about DPFs. For every owner that has a DPF issue, there'll be hundreds or thousands or owners who have no issues.

I'll offset the skew then

I have a XC90 with the D5 diesel engine with DPF with no issues whatsoever

It's been through a number of regen cycles whilst I have owned and driven it over the last 10000 km, never noticed a regen and never was an issue.

[Oil Burner]

Ok, lets talk re-gen's then.

If I had a diesel with a DPF and taking into account my current daily driving of 8 miles to work and 8 miles back.

If the car suddenly decided to start a re-gen what do I do?

Do I just carry on home, switch off and go to work the next day hoping things just 'work out' or do I when the regen starts take a long detour home in order to allow the re-gen to do its stuff.

If it's the latter, and stopping a re-gen before completion due to my current daily mileage then this confirms the theory and stories in the journalistic internet sites that diesels are a no-go option for people driving less than 25 mins each day and requiring a long motorway drive to 'fix the issue'

Besides, what happens to people who do not have any motorways or fast roads where they live in order to complete a re-gen?

[Clan]

Originally Posted by Oil Burner

Hi all,

Some really good discussion points being raised in this thread.

But to my original concerns/fears.

Yes my S60 (2005) has plenty of life left in it (hopefully). I was just looking at my options for a newer car before more things go wrong.

Yes I know it is cheaper to fix the odd problem each year for a few hundred pounds at a time over paying out 10-14k for a approved used car.

My concern with diesel in particular was in buying a Volvo Selekt used car of 2-3 years old that has just come out of lease and not knowing if the car has never been out of a ten mile radius of its home address and within a few months be plagued with DPF regen issues etc.

I would be more comfortable maybe with a higher mileage car out of lease that has done some serious miles to keep the DPF clear. But then again if reading on the internet is true, DPF's need physically changing after about 75k miles as they are past their service life.

This point is also linked to my original post whereupon I believe many owners will be offloading their cars as they near this mileage as they do not wish to pay for a new DPF and the new 'unsuspecting' fool who buys it has to pay for a large repair cost in possibly their first year of ownership.

Not True, only the 1.6 and 2.0 FORD based engines up to about 2010 need to have this done , Later ford engines and all volvo ones have a Particle filter that lasts a long long time .

[taz777]

Originally Posted by Oil Burner

Ok, lets talk re-gen's then.

If I had a diesel with a DPF and taking into account my current daily driving of 8 miles to work and 8 miles back.

If the car suddenly decided to start a re-gen what do I do?

Do I just carry on home, switch off and go to work the next day hoping things just 'work out' or do I when the regen starts take a long detour home in order to allow the re-gen to do its stuff.

If it's the latter, and stopping a re-gen before completion due to my current daily mileage then this confirms the theory and stories in the journalistic internet sites that diesels are a no-go option for people driving less than 25 mins each day and requiring a long motorway drive to 'fix the issue'

Besides, what happens to people who do not have any motorways or fast roads where they live in order to complete a re-gen?

To be honest, I think you're worrying too much!

The car will work out when it needs to do a regen. I have a 1-year old S80 so it's fairly modern. It detects if a regen is needed and whether the driving conditions are right for a regen. If they are then it does a regen. If the driving conditions change suddenly so that they are not suitable for a regen then the regen stops and it continues when they are met again.

In some circumstances it isn't able to do a regen 'in the background' (i.e. without you being aware that one is needed/being done). The soot filter gets more full.

In that case it issues a warning to you. You get the engine up to temperature and do a steady, long drive on a motorway for 20-40 minutes. The warning should go out after that drive.

If the soot filter cannot be cleared then that will be bad news. Given the number of diesel vehicles on the road versus the number that have to go to a workshop to have the DPF cleaned or even replaced, it's not a big issue.

Just do a long, steady, fast 40-50 mile drive once a week and I think you'll be fine. I use the opportunity to learn more about the car when I do my weekly long drive (thinks like the voice control, navigation, etc).

[mordred1973]

Does anyone have a reasonable gauge on when a DPF does need replacing? My D5 must have undertaken numerous regens in the last 72000 miles but I have not been aware of any , (other than after one trip found a very light soot deposit on the front of the caravan)

Does the DPF of a 2012/13 engine just keep going for a reasonable mileage?

[Clan]

Originally Posted by mordred1973

Does anyone have a reasonable gauge on when a DPF does need replacing? My D5 must have undertaken numerous regens in the last 72000 miles but I have not been aware of any , (other than after one trip found a very light soot deposit on the front of the caravan)

Does the DPF of a 2012/13 engine just keep going for a reasonable mileage?

they go on and on as they should , there is no change period and they are very reliable in general .Much like the cataylic converters do which no one ever talks about .