Diesel car about town

nightster1

Can anyone tell me why I should use my diesel car for long distance trips rather than about town. I drive a 2004 model BMW 3.0D 6 cyl auto for the last 9 years. There's 150k miles up on her now. Most of this driving is in city traffic with the odd run out of town. I've never had to do any mechanical work to her other than routine maintenance. She has never needed a top up of oil between services, which I get done every 10k. A lot of my trips are for a few miles with cold starts. London cabs are auto diesels, I fail to see a prob!!!

Dr. Kenneth Noisewater

I'm no expert but as far as I know its more new diesels (08 onwards) that would give you problems with DPFs which would clog up with carbon soot from not getting a good driving to regenerate them (i.e. blow all the crap out of them).

dgt

I think its more short trips rather than city work. My 406 does a lot of city driving but I've the cat cut off. No problems there either. It'd be ran for hours though

deandean

That's largely because your 9-year old car has no DPF and no DMF I'd say

Bpmull

As said the only issue with taking a diesel on constant short trips /city driving is if it has a dmf dpf. If it doesn't have either then there shouldn't be any trouble. I know what mean op as going by some posts on here you would swear a diesel car would blow up if it was doing city driving for more than 5 minutes.my diesel gets plenty of town driving and has no problem but it gets plenty of long trips too and doesn't have a dpf.

The only other thing is even with older diesels it would be pointless to pay the extra premium for a diesel car if it was only getting short drives all the time. As diesels arnt efficient when driving short trips as they take longer to warm up than petrols which would mean there would be little mpg benefit to driving one on short trips only.

MuppetCheck

I don't think there's a dpf and there wont be a dmf so a lot less to go wrong with city use on your car. It's the newer ones that have the potential to cause issues.

nightster1

deandean wrote: »

That's largely because your 9-year old car has no DPF and no DMF I'd say

I wonder why the DFP & DMF are fitted in modern cars then? I guess its for emissions. Many people are buying modern diesels now for the lower tax and then suffering high repair costs with engine problems. A friend of mine had a flywheel fail on a diesel Passat recently. Petrol models don't have this prob apparently. Another friend was told that his new avensis diesel needs a good run to heat up the catalytic converter, as short runs had the exhaust piling out clouds of white smoke.

My old diesel runs as good as new or maybe better, I change the filters incl engine breather regularly and use high spec oil at service times.

Marcusm

The DPF was invented to deal with the increase in asthma and other respiratory illnesses which have been, in part, attributed to the increase in soot particulates from an increase in diesel usage - think of it as a car equivalent of smokeless coal. A new issue may be on the horizon as there is concern that the tinier particulates which get through the DPF may contribute to lung cancer.

The DMF as I understand it helps to smooth out the vibrations of the diesel engine being transmitted through to the passenger cabin. Something to do with two different densities of metal transmitting fewer vibrations than a single (steel) one.

TBi

Marcusm wrote: »

The DMF as I understand it helps to smooth out the vibrations of the diesel engine being transmitted through to the passenger cabin. Something to do with two different densities of metal transmitting fewer vibrations than a single (steel) one.

Dual mass flywheel has springs between the two masses. No fancy metals, just springs smoothing out the engine.

Jesus.

I wonder about that too tbh. Practically every van you see doing crazy city mileage is a diesel. You just don't hear of Companies buying petrol vans because there might be a lot of city driving.

All industrial vehicles are daysul including buses

CiniO

nightster1 wrote: »

Can anyone tell me why I should use my diesel car for long distance trips rather than about town. I drive a 2004 model BMW 3.0D 6 cyl auto for the last 9 years. There's 150k miles up on her now. Most of this driving is in city traffic with the odd run out of town. I've never had to do any mechanical work to her other than routine maintenance. She has never needed a top up of oil between services, which I get done every 10k. A lot of my trips are for a few miles with cold starts. London cabs are auto diesels, I fail to see a prob!!!

There is nothing wrong happening to your car - that's allright.
But considering your only short city trips, you could as well have bought petrol car, which would have lower maintenance cost and purchase value.
I can't imagine you saving any cash on fuel, by doing short city runs in a diesel.

Interslice

Jesus. wrote: »

I wonder about that too tbh. Practically every van you see doing crazy city mileage is a diesel. You just don't hear of Companies buying petrol vans because there might be a lot of city driving.

All industrial vehicles are daysul including buses

DPF requires heat from load(right foot) or exhuast injection to regenerate, not nessecarily a motorway. Buses are generally automatic so no DMF. Vans etc. will generally have a bit of weight in them and be buzzing around town inside rush hours creating plenty of heat in the exhaust. Constant heavy traffic would be bad.

Jesus.

Interslice wrote: »

Vans etc. will generally have a bit of weight in them and be buzzing around town inside rush hours creating plenty of heat in the exhaust.

Good attempt Interslice but I don't buy it

bazz26

I don't think commercial vehicles up to recently were required to have a DPF fitted.

visual

nightster1 wrote: »

Can anyone tell me why I should use my diesel car for long distance trips rather than about town. I drive a 2004 model BMW 3.0D 6 cyl auto for the last 9 years. There's 150k miles up on her now. Most of this driving is in city traffic with the odd run out of town. I've never had to do any mechanical work to her other than routine maintenance. She has never needed a top up of oil between services, which I get done every 10k. A lot of my trips are for a few miles with cold starts. London cabs are auto diesels, I fail to see a prob!!!

There isn't any problem most taxis are diesels and have no issues

The only concern is with more modern diesels fitted with DPF. That need a fast run every so often to regenerate the DPF

Interslice

Jesus. wrote: »

Good attempt Interslice but I don't buy it

I swear to Jesus;).

In a loaded up van, down hill at 60mph in 5th your exhaust would be colder than up a steep hill at 20mph in 2nd. The engine load is greater so more air more fuel and more heat.

Jesus.

Tis a very worthy effort, honest to God Interslice. Respect bro.

None of these explanations cut it though when you consider the amount of high mileage daysuls that have been doing City driving since their birth and they're still in grand working order. Taxi men and small van drivers will attest to that!

nightster1

Having a car or commercial with a dpf fitted doesn't sound like a good idea. Your use of the vehicle is compromised. You can't drive as you please, but must take a run out of town every so often to heat up the dpf. A better idea needs to be invented. What a waste of diesel, if you have to take a spin for the benefit of the engine