Is it worth getting a Diesel?

jonbeeza

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I have done a search on this forum already, a lot of stuff on Diesels but not found anything specific about the pros and cons of getting a Diesel. We have had two diesel cars over the last few years, and about to replace it with another. When we first used Diesel years ago it was cheaper, but now the fuel is more expensive than Petrol plus we always get filthy hands at the pumps. Plus there is always talk of phasing Diesel vehicles out, so it seems it is not so popular any more..

Wonder if we should go petrol, may save money in the long run :thinking:
 
Most sources say unless you're doing 20K+ miles per year the additional costs of diesel ownership don't make them cost effective.

However...... I used to own a 1.8 petrol Focus but switched to a newer (by 5 years) 2.0 TDCI Focus. I used to get low 30s MPG from the petrol but generally get low 40s with the diesel, this is saving me between £50-£100 per month. VED is around £90 a year less too.

Running costs wise, having lots of torque and a big heavy lump over the front wheels I'm replacing the front tyres every 11K-12K miles (18" wheels so anything half decent is £70+ each) but servicing/repairs seem to be around the same as the petrol.

However......... a lot of newer diesels have a DPF (mine doesn't) and dual mass flywheels (DMFs), both of which are expensive to replace (I know on mine the clutch & DMF replacements is around £900 worth of work), not sure if it's just a Ford-Diesel thing or not but apparently the injectors are prone to failure after around 90K miles and that's a delightful £800-£900 repair bill.

It would seem the smart way to go is one of the newer small-turbo engines, although I've had it on good authority that these can be prone to failure as they're quite highly strung.

I know I'm going to be in a similar situation as you in the next few years as mine's nearly 11 years old. I really can't afford (or want) to spend any more a month on fuel but the newer, more efficient petrol engines are going to still be out of my price range.

I can also see a point in time, not too far ahead where older/bigger diesels will be pretty much taxed off the road :/
 
I have done a search on this forum already, a lot of stuff on Diesels but not found anything specific about the pros and cons of getting a Diesel. We have had two diesel cars over the last few years, and about to replace it with another. When we first used Diesel years ago it was cheaper, but now the fuel is more expensive than Petrol plus we always get filthy hands at the pumps. Plus there is always talk of phasing Diesel vehicles out, so it seems it is not so popular any more..

Wonder if we should go petrol, may save money in the long run :thinking:
A blanket answer is not possible. How many miles are you doing, what diesel car and what petrol car will you be comparing?

Unfortunately it isn't possible to give a generic answer.
 
Due to Russ's points about DPF's and DMF's, after years of owning a diesel I'd now go back to petrol I think. I also only do about 9000 a year so diesel probably not needed. The £20 Tax and 45+ mpg is nice while it lasts though.

As well as DJ's points, whether you are buying new or second hand is another factor.
 
If you generally do only short distances watch out for Diesel Particulate Filter (DPF) issues. Also, there is a strong possibility of increases in diesel fuel duty within the next year or so. Plus "clean zone" charges if you go into many cities.
 
As dejongi says, you'd need to provide more info to get anything like accurate advice, plus remember that official fuel consumption figures can be laughably overstated for real world driving, possibly by 10-20%.
 
Most sources say unless you're doing 20K+ miles per year the additional costs of diesel ownership don't make them cost effective.

However...... I used to own a 1.8 petrol Focus but switched to a newer (by 5 years) 2.0 TDCI Focus. I used to get low 30s MPG from the petrol but generally get low 40s with the diesel, this is saving me between £50-£100 per month. VED is around £90 a year less too.

Running costs wise, having lots of torque and a big heavy lump over the front wheels I'm replacing the front tyres every 11K-12K miles (18" wheels so anything half decent is £70+ each) but servicing/repairs seem to be around the same as the petrol.

However......... a lot of newer diesels have a DPF (mine doesn't) and dual mass flywheels (DMFs), both of which are expensive to replace (I know on mine the clutch & DMF replacements is around £900 worth of work), not sure if it's just a Ford-Diesel thing or not but apparently the injectors are prone to failure after around 90K miles and that's a delightful £800-£900 repair bill.

It would seem the smart way to go is one of the newer small-turbo engines, although I've had it on good authority that these can be prone to failure as they're quite highly strung.

I know I'm going to be in a similar situation as you in the next few years as mine's nearly 11 years old. I really can't afford (or want) to spend any more a month on fuel but the newer, more efficient petrol engines are going to still be out of my price range.

I can also see a point in time, not too far ahead where older/bigger diesels will be pretty much taxed off the road :/
A blanket answer is not possible. How many miles are you doing, what diesel car and what petrol car will you be comparing?

Unfortunately it isn't possible to give a generic answer.

We do well under 20k a year, probably more like 10 maybe 12K a year. Certainly do not do many miles per year, but looking at an MPV sized vehicle as we need the size. Something like a medium sized vehicle. But will go and have a look tomorrow I think.
 
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Not much in it anymore with some of the new eco turbo petrol's. Then when you need new injectors and DPF on your diesel it eats up any savings that might have been and some :).

P.s they are fast becoming the bad guys and likely to start getting a hammering. VW are releasing a petrol transporter this year i think the wind is changing.
 
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We do well under 20k a year, probably more like 10 maybe 12K a year. Certainly do not do many miles per year, but looking at an MPV sized vehicle as we need the size. Something like the Ford Tourneo connect, they reckon the diesel are supposed to be good on the fuel, or at least a little better than the petrol. But will go and have a look tomorrow I think.
For that size of car I would guess for drivability that even the entry level diesel is better; much more torque, less CO2, better MPG and only 30Kg heavier. But without driving it is hard to tell.

From a cost perspective based on 12K/annum average price from today on petrol prices
Petrol - £1,207.75
Diesel - £1,035.49

Taking the cheapest list prices:
Petrol - £14,495.00
Diesel - £15,645.00

So you are £977 better off in the first year with the Petrol. Then £172.26 better off per year with the Diesel. So you'll need to keep the diesel 5.7 years before you break even ;)

However this doesn't take into account servicing and insurance. And to me for such a small difference; drivability. Only you can judge that when you test drive. Enjoy choosing!
 
For that size of car I would guess for drivability that even the entry level diesel is better; much more torque, less CO2, better MPG and only 30Kg heavier. But without driving it is hard to tell.

From a cost perspective based on 12K/annum average price from today on petrol prices
Petrol - £1,207.75
Diesel - £1,035.49

Taking the cheapest list prices:
Petrol - £14,495.00
Diesel - £15,645.00

So you are £977 better off in the first year with the Petrol. Then £172.26 better off per year with the Diesel. So you'll need to keep the diesel 5.7 years before you break even ;)

However this doesn't take into account servicing and insurance. And to me for such a small difference; drivability. Only you can judge that when you test drive. Enjoy choosing!

Certainly something to to think about, thanks for the figures :).

Will probably go and have a look at our local Ford dealer tomorrow. I will probably just go with what the missus wants, it is far easier :rolleyes:
 
Having had hybrid cars I would say if you do town driving get a hybrid, if you do long journeys get a diesel.
My experience with the Prius was very different. Great on long distance journeys, I got easily 72mpg measured out of it. Around town with all the hills around where I live the engine was screaming and uncomfortable to get going. Then there was the depreciation. We were lucky to get 50mpg out of it. My Golf R does only 10mpg less than that.
 
I switched about 2 years ago from a C3 diesel to a C3 petrol.
Yes you spend more on fuel but the vehicle was a lot cheaper.
There is less to go wrong, its much quieter and warms up quicker in winter.
the VED is a bit more but nothing major.
I actually ended up doing more miles than I expected but I am still glad I made the change.
I like to think I am environmentally aware and for me that was a big factor, diesel is very dirty and as per the VW scandal the truth is out.
 
For that size of car I would guess for drivability that even the entry level diesel is better; much more torque, less CO2, better MPG and only 30Kg heavier. But without driving it is hard to tell.

From a cost perspective based on 12K/annum average price from today on petrol prices
Petrol - £1,207.75
Diesel - £1,035.49

Taking the cheapest list prices:
Petrol - £14,495.00
Diesel - £15,645.00

So you are £977 better off in the first year with the Petrol. Then £172.26 better off per year with the Diesel. So you'll need to keep the diesel 5.7 years before you break even ;)

However this doesn't take into account servicing and insurance. And to me for such a small difference; drivability. Only you can judge that when you test drive. Enjoy choosing!

Assuming you DPF doesn't clog up and need to be manually regenerated or even replaced.
 
Assuming you DPF doesn't clog up and need to be manually regenerated or even replaced.
As I said doesn't include servicing ;) but then again it can easily be avoided.
 
Certainly something to to think about, thanks for the figures :).

Will probably go and have a look at our local Ford dealer tomorrow. I will probably just go with what the missus wants, it is far easier :rolleyes:
If you're after a connect do they even do a petrol?
 
Assuming you DPF doesn't clog up and need to be manually regenerated or even replaced.
True, and I think that can have more to do with your typical journey rather than overall annual mileage. For instance it's very rare, due to where I live, that any trips in the car are less than 8-10miles - so there's enough time for the engine to get up to proper operating temperature (I think). Whereas you could do loads more miles a year than me but have each journey as only a couple miles, which would be much worse for the DPF.
 
If you're after a connect do they even do a petrol?
Yes a 1.0 ecoboost. Where do you think I got the comparison figures from ;) from their website.
 
True, and I think that can have more to do with your typical journey rather than overall annual mileage. For instance it's very rare, due to where I live, that any trips in the car are less than 8-10miles - so there's enough time for the engine to get up to proper operating temperature (I think). Whereas you could do loads more miles a year than me but have each journey as only a couple miles, which would be much worse for the DPF.
Just make a couple of nice journeys and none of this has to be an issue. Short journeys aren't great for most cars including petrol from different perspectives.
 
True, and I think that can have more to do with your typical journey rather than overall annual mileage. For instance it's very rare, due to where I live, that any trips in the car are less than 8-10miles - so there's enough time for the engine to get up to proper operating temperature (I think). Whereas you could do loads more miles a year than me but have each journey as only a couple miles, which would be much worse for the DPF.

It's not just about getting the engine up to temperature though. You need to get the exhaust up to the right temperature.
From what I understand a long journey at 30-40MPH isn't going to build up enough heat to regenerate the DPF. You'll need to find a motorway and get the engine up to speed.

It's one of the reasons I won't buy a Diesel. I'd have to drive 30 miles just to find a motorway and even that's normally at a stand still. (The M4)
 
If you're after a connect do they even do a petrol?
I did think something like the Connect, but something like a mid sized MPV. I have got my eye on a few, but the missus thinks the ones I like are ugly. I like van type vehicles, but she hates them :(
 
We have a 55 reg Octavia 1.9 TDi PD model, and it is the most economic car we have ever owned.
It did have a DMF, which I replaced with a solid flywheel and clutch (£350) at around 94K miles (it has now done nearly 150K)
It doesn't have a DPF
It doesn't have an EGR
It is lower tax and insurance than my previous 18 Mondeo petrol.
It does at least 51MPG and sometimes around 57MPG on a long run, and maintains that economy at European motorway speeds.
 
We have a 55 reg Octavia 1.9 TDi PD model, and it is the most economic car we have ever owned.
It did have a DMF, which I replaced with a solid flywheel and clutch (£350) at around 94K miles (it has now done nearly 150K)
It doesn't have a DPF
It doesn't have an EGR
It is lower tax and insurance than my previous 18 Mondeo petrol.
It does at least 51MPG and sometimes around 57MPG on a long run, and maintains that economy at European motorway speeds.

That was one of the reason we always bought Diesel, for the good fuel economy. Plus we always thought Diesel engines were more robust. Will have a look at both tomorrow I think, if we get to go to the garage that is..
 
True, and I think that can have more to do with your typical journey rather than overall annual mileage. For instance it's very rare, due to where I live, that any trips in the car are less than 8-10miles - so there's enough time for the engine to get up to proper operating temperature (I think). Whereas you could do loads more miles a year than me but have each journey as only a couple miles, which would be much worse for the DPF.

what he said, its more about length/type of journey than annual milage. depending on what manufacturer you listen to some suggest at least 10 mins at 40mph+ others say longer periods at a higher speed.

some diesels have a built in system to "regenerate" the DPF in the case that your journey does not get the system hot enough. although personally I wouldn't recommend relying on this, your fuel economy will suffer for one and it will not always work if the journey is less than 20 mins.

watch out for dual mass flywheels too, some makes of diesels have ones made from chocolate. my VW with the PD140 (2.0 16v) for example which set me back £900. and warrantys rarely cover them unless you can prove a manufacturing fault over wear and tear.
 
It's not just about getting the engine up to temperature though. You need to get the exhaust up to the right temperature.
From what I understand a long journey at 30-40MPH isn't going to build up enough heat to regenerate the DPF. You'll need to find a motorway and get the engine up to speed.
At 70mph you'd be at around 2000rpm in 6th. You can get the exhaust just as hot or hotter at 30-40mph just by keeping it in a lower gear.
 
Too short a journey in a diesel where it doesn't warm up properly will dilute the oil. On some Ford diesels the ecu monitors this by the number of starts and length of running time. It's not uncommon on low use cars for an oil service message to come up on the dash as a result.
 
We do well under 20k a year, probably more like 10 maybe 12K a year. Certainly do not do many miles per year, but looking at an MPV sized vehicle as we need the size. Something like a medium sized vehicle. But will go and have a look tomorrow I think.
Would a Ford B-Max be big enough or is it too small. This is also available with the 1.0 Ecoboost. I'm not 100% sure but it maybe being phased out in a year or so, which may mean some good deals available. If you can find a vehicle to your (wife's) liking and in stock, don't forget the end of the month is on it's way, they will be wanting to increase their sales bonus.
 
Would a Ford B-Max be big enough or is it too small. This is also available with the 1.0 Ecoboost. I'm not 100% sure but it maybe being phased out in a year or so, which may mean some good deals available. If you can find a vehicle to your (wife's) liking and in stock, don't forget the end of the month is on it's way, they will be wanting to increase their sales bonus.
Probably too small, as will be needing to get an electric chair in the rear at times. I was thinking an MPV would be better for this, although I would simply go for a medium sized van. But the missus does not want to be going out in a van.
 
Probably too small, as will be needing to get an electric chair in the rear at times. I was thinking an MPV would be better for this, although I would simply go for a medium sized van. But the missus does not want to be going out in a van.
:eek: remind me to never be a passenger :P
 
I can feel when my DPF needs regen. As nilagin says, normal driving, normal distance, but using lower gears to keep the revs up clears up the hesitation very quickly.

The car has DMF too. I think the issue with those is people using the healthy torque to labour the engine, in low gears. You can feel the judder when you do that, avoid that & problems seem rare.
 
I can feel when my DPF needs regen. As nilagin says, normal driving, normal distance, but using lower gears to keep the revs up clears up the hesitation very quickly.

The car has DMF too. I think the issue with those is people using the healthy torque to labour the engine, in low gears. You can feel the judder when you do that, avoid that & problems seem rare.

Our cars are always auto as my missus is an auto licence holder, wonder how that would work. Select 1 or 2 and keep it there? Tend to just select drive and go, prefer driving manual but gotta think of the missus :)
 
Our cars are always auto as my missus is an auto licence holder, wonder how that would work. Select 1 or 2 and keep it there? Tend to just select drive and go, prefer driving manual but gotta think of the missus :)
Nah just drive it normally. It will sort itself out.
 
Not sure that's the case, especially these days. Diesel engines aren't the heavy cast-iron blocks of old.
My mate had an Austin Montego, rubbish body but a cracking engine. It was fitted with a Turbo Diesel Perkins engine, body soon rotted away and engine was snapped up by a dealer..
 
The car has DMF too. I think the issue with those is people using the healthy torque to labour the engine, in low gears. You can feel the judder when you do that, avoid that & problems seem rare.

never do/did that. unless the previous owner did, but it was very low milage so doubt it. the PD140 is well known for DMF failures too.
 
If I was driving a petrol, not diesel Passat my fuel would cost me like a couple thousand more per year. This is not an exaggeration, and my site proves it :) LPG conversion would be the only thing that could save the bank after the initial cost of nearly £2k. :( 4 cylinder petrols tend to feel very low in low end power vs diesels unless they are some bigger turbo sport versions, or at least a good V6. I reckon I will just go straight to electric / electric-hybrid when the time is right, maybe in 5 years time.

I have done a search on this forum already, a lot of stuff on Diesels but not found anything specific about the pros and cons of getting a Diesel. We have had two diesel cars over the last few years, and about to replace it with another. When we first used Diesel years ago it was cheaper, but now the fuel is more expensive than Petrol plus we always get filthy hands at the pumps. Plus there is always talk of phasing Diesel vehicles out, so it seems it is not so popular any more..

Wonder if we should go petrol, may save money in the long run :thinking:

1. Petrol and diesel costs about the same right now in most pumps. Diesel is usually 1p less. In most of Europe diesel costs quite a bit less.

2. Almost all pumps provide disposable gloves. It is rather unwise not to use them. Petrol is not much better for the skin (a carcinogen before you even consider all super harmful additives in the premium version)

3. Diesels are not going anywhere in the next 3 years, unless you live in London. If so you'd be wise to get electric/hybrid or at the very least brand new Euro VI diesel - combating congestion charge being the prime reason.

Due to Russ's points about DPF's and DMF's, after years of owning a diesel I'd now go back to petrol I think.

DPFs problems vary greatly across different cars. It is best to do research and buy the more reliable ones.

DMF is likely to go in any car between 90-150k. You then replace it with single mass kit, or even better you buy an auto and never have to worry about the stupid thing and the stupid manual transmission (there is a flywheel in dual clutch autos... buy one that doesn't rattle!)


PD140 is well known for DMF failures too.

Horrible engines; all late VAG PDs including the last 1.9TDI (BXE) are seriously temperamental. The later (58+, the ones affected by scandal) Common Rail engines are far superior

It is however comforting to know that most VAG engines come in rather cheap from scraps and there is a plentiful supply should the worst happen. In comparison try finding an affordable Range Rover, Jag or even a Mazda unit. They don't exist.
 
My mate had an Austin Montego, rubbish body but a cracking engine. It was fitted with a Turbo Diesel Perkins engine, body soon rotted away and engine was snapped up by a dealer..

Probably in a narrow boat now, a reasonably common application. (I never got to work on one during my time on the canals, but they were generally hated as being very finnicky things by the others at the yard).

My Dad swears by diesels for his commute of 100 miles daily, where he is currently getting 50-60mpg out of a 2.2CDTi Civic, it's not slow either, at least on turbo anyway. (Boot it in 2nd and it will easily leave my FTO standing, just a shame it won't go round a bend!)
 
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