Looking at a new car and unsure if a diesel car will be better in the long run … I do 200 miles a week travelling to work , so do around the 10k mark each year … will diesel be a better option ? …. is there something like an online calculator to work it out ?

I think diesels are better if you’re doing some long journeys rather than lots of short trips.

And take into account how long you’ll own the vehicle when considering the purchase costs.

it depends. 200 miles / week = 20 miles each way, assuming you don’t do any private mileage at the w/e or in the evenings. if more than half of that is motorway / fast open road, then maybe.

if it’s stop-start city driving all the way then probably not. Especially if it has a DPF

My commute 40 odd miles a day,plan on keeping the car for at least 5 yrs .. until it dies 😀
its a mix of dual carriage ways and city driving …

For 10k miles a year a diesel will be cheaper on fuel and tax, but more expensive to buy, repair and service. This is all relative to the age of the car.

If you’re only planning to keep it a short while you’ll likely get the extra expense required to purchase, back again at the time of sale.

If you plan to keep it until it dies then look at the equivalent petrol and calculate the price difference, then take the fuel cost for the diesel over 10k vs the fuel cost for the petrol over 10k. Subtract the diesel cost from the petrol cost and then divide the difference in purchase cost by the difference in the fuel cost and it’ll give you an figure equal to the number of years to the break even point.

EDIT:

Something else to consider: All 3 of my petrol cars come VERY close to claimed manufacturer figures for MPG. My diesel is about 20-25% down on what the manufacturer claims.

What type of car?
The smaller the car, the less likely diesel is worth it, especially as the price differential is quite high at present
http://www.which.co.uk/cars/driving/driver-tools/petrol-vs-diesel/petrol-and-diesel-fuel-costs/
http://www.which.co.uk/cars/choosing-a-car/buying-a-car/petrol-or-diesel/

The cars only going to be small super mini, seat ibiza, kia rio,corsa etc ..

another thing to consider…

I had a 320d Tourer and then a 9-3 1.9TiD estate, both averaged around 42mpg on a 28mile each way commute – 8-10 miles urban, the rest motorway. Manufacturers estimates in the mid 50s for both.

I got rid of the Saab as I couldn’t (at the time they came due) afford the new cambelt & 4 new tyres at the same time.

I’m now driving Mrs_d’s Citroen C4 1.6 Petrol on the same journey & getting about 36mpg. Working it out the diesels gave me one sixth, i.e 16% better economy, for about 3-5% more pence per litre.

I understand the very latest diesels are even more frugal. or so they like to tell us.

The calculation is already built in to car prices, second hand anyway. But it will be based on average mileage. 10k sounds less than average so petrol probably cheaper.

We have a sort of a mini fleet of family cars & vans.

If its new and stays under warranty while you have it – a diesel is cheaper (if you dont mind the odd garage visit to investigate some TLA youve never heard of).

If outside warranty, you do a lot of miles – a diesel will /may work out cheaper – but can have some big bills.

If you do lower miles and / or are buying outside warranty, a petrol is more economical ime.

Petrol

I had a 320d Tourer and then a 9-3 1.9TiD estate, both averaged around 42mpg on a 28mile each way commute – 8-10 miles urban, the rest motorway. Manufacturers estimates in the mid 50s for both.

That’s a bit pants, I get 55-65 out of my diesel though similar driving and a 1.9.

Do you have dents in your car under your right foot?

Smaller car mind, Golf.

Just to counter the diesel fuel economy being off for some folk, I get the claimed mpg out of my diesel.

Drive like a granny and I exceed it.

It depends how much you pay for it, which will really decide the actual cost.

I do about the same mileage as you and have ran big petrols for a while now, cheap to buy/keep/service but expensive in fuel.

And mpg barely changes however you drive, this side of stealing it 🙂

At 10K a year it won’t be decisive either way tbh.

I chose a diesel because it drives so nicely, though.

At that milage – petrol. If you care about costs get something smaller engined – say around 1300cc. Lots of really good small cars these days. If you buy the right brand at 5yrs old and 50k miles it should drive and look like new.

FWIW we have both petrol and diesel cars, the diesel does 25k a year, the petrol cars less than 10k

Actually, we test drove an Ibiza ecomotive diesel. It’d be a brave move to overtake anything in one of those.

And I’m talking tractors, mobility scooters, road kill. That sort of stuff.

@ piemonster …. really that bad ?? …. was one we were considering 🙁

That’s a bit pants, I get 55-65 out of my diesel though similar driving and a 1.9.

Do you have dents in your car under your right foot?

heh heh, no 🙂 I drive like your grandad

When I say “urban” I mean through Leeds/Bradford during the morning and evening rush hours. Well over a million people live between my house & the motorway network, and they all seem to want to go to the same places as me at the same time 🙁

The beemer was an 04 plate and the Saab a 57 so not the very latest diesel technology. I’ve also managed to get rid of about 60kg (or more) of cymbal stands from the boot since I started driving the Citroen, they’re all permanently set up in the rehearsal room, so that would have had some effect on the fuel consumption.

Stumpy, to be honest I’d not compared it to any of the other lawn mower type cars of that ilk.

But my lasting memory is thinking “we’ll, I hit the accelerator, maybe it’ll go quicker if I fart out the window at an appropriate angle”

For 10k a year, and looking at Super Minis I’d be tempted to go with a city car. VW Up or similar.

Also, in contrast to my post on MPG, I doubt you’ll get the claimed mpg out of the Ibiza Eco. We was told that immediately by the Seat salesman.

John, yeh, actually that mpg looks entirely reasonable.

I get to use cruise control on a regular basis on my dual carriageway and motorway journeys. Different roads.

I would go petrol. I have a similar commute to you 40mi round trip motorway for 15miles and 5miles of suburban/urban. The only thing that makes my diesel pay is the business miles I periodically drive and regular 400mile round trips to visit family, which takes my annual mileage to between 15 and 20k a year. The diesel car is harder on tyres, the controls (clutch and gearbox) are heavier and it is less sharp to drive.

It really comes into its own for the proper long haul stuff (50miles+).

My comments above on the relative diesel/petrol merits is based on our 2 mondeos of similar vintage and mileage, one is a 1.8petrol hatch the other a tdci estate. In smaller cars I always think a fizzy petrol is the way to go. A heavy diesel just seems wrong (purely a heart thing no science reason).

Ultimately at 10k and a 40 mile round trip I would have thought you could go for either without issue but one or other will cost you more. If you have to do 40 miles a day in it at rush hour I woild go with what I preferred to drive over pure cost.

Petrol

If you have to do 40 miles a day in it at rush hour I woild go with what I preferred to drive over pure cost.

+1 – you’re in the car for a long time (well, I can be. roadworks on M62 + breakdowns/accidents mean a 50min journey can suddenly become 2hrs or more) – you HAVE to be comfortable.

To be fair, both the diesels and the Citroen have cruise control, I wouldn’t buy a car without it these days. apart from the obvious, it helps avoid speeding tickets…

i have a 2.0 mondeo diesel, average over 150,00 miles is just over 50mpg.
my previous fiat punto 1.3 diesel managed 53mpg over 65,000 miles.
a 1.2 petrol will likely do close to 50mpg but be a bit cheaper to buy/run.
diesel will be better to drive though, much more torque.

Petrol at 10K miles per year – no clear benefits for diesel until you hit 18K+ miles per year. Plus lots of short diesel journeys clog up the particulate filters.

But my lasting memory is thinking “we’ll, I hit the accelerator, maybe it’ll go quicker if I fart out the window at an appropriate angle”

Thats nothing. I once test drove a Smart FourFour for the missus to use as a runabout. I could have walked faster. Following day bought a Polo GTI.

For very urban driving, definitely consider hybrid. On the open road, both my diesel and hybrid can get 60mpg. In heavy traffic the hybrid can do 54mpg, the diesel drops to 38mpg.

no clear benefits for diesel until you hit 18K+ miles per year

I dispute that. As for the short journeys – that’s true, but we’re talking very short journeys, like 2 miles to the shops.

Diesel every time for me, purely as a personal preference. 230bhp, 330lb/ft torque (450Nm), sub 7s 0-60, 60+ mpg on 70mph motorway with cruise control, still 50+ mpg at motorway “outside lane speeds”.
Good torque makes for easy overtaking on rural roads too. Hate to see cars try to overtake & still in same place at end of straight, having barely got alongside…decide quickly, get out, get past, get in & reduce speed from overtake.
If short urban journeys only & no longer journeys / open roads, then small petrol engine makes most sense.

I did about 25k last year (a one off, I’ll probably do 6-8k this year), I bought he car specificaly to do that but got a petrol as it what the local garage had and I wanted the car there and then not shopping arround and tyre kicking for 2 weeks.

At the end of the year I reckoned I’d ‘lost’ about £300 over the equivelent diesel when the difference in purchase and resale prices were accounted for.

50mpg would be nice day to day, but it still does 42mpg (it’ll only do the claimed 50+mpg if you draft a lorry) on the motorway and 35 on my b-road commute so I’m not too dissapointed as I’d not have got a nearly new diesel for what I paid for a nearly new petrol.

Depends how much you are spending too.

If you are buying new, or nearly new, theres not much to lose with diesels and most stuff covered under warranty.

2nd hand older cars risk lots of big bills though. Not all diesels have stuff going wrong, but the ones that do tend to get sold. Any turbo car is more complicated too, so lots more to check.

I would say you’re in a better position if you’re NOT buying nearly new. If your budget is £8k or whatever, you can get a diesel or a petrol for the same price, just the diesel will be a bit older. And in the grand scheme of things, if you are keeping it for a while, that doesn’t make much difference.

It’s worth noting that an occasional long run keeps a diesel happy, so if you go places on weekends that will sort it out. It’s if you ONLY do really really short trips that you may have an issue.

Diesel every time for me, purely as a personal preference. 230bhp, 330lb/ft torque (450Nm), sub 7s 0-60, 60+ mpg on 70mph motorway with cruise control, still 50+ mpg at motorway “outside lane speeds”

Blimey, what car’s that? I’m guessing something bloody expensive!

I sat annd did the sums 3-4 years ago on a Seat Leon, petrol v diesel, when I thought I was going to get a job with a lot of driving and a car allowance. On a NEW Leon at the time I wouldn’t have made diesel pay until I’d done 60,000 miles.
Now, fuel prices have changed since then, so that will have changed, maybe 50,000 miles until payback. If you keep your cars for a long time and/or do lots of miles then its worth it. 10k/year and changing every 2-3 years? Nope. Doubt it.

DezB – tuned 😉 BMW

On the subject of small petrol engines – I hired a Clio 1.2 3cyl in Dublin last year. It was SO slow that to get up to speed on motorways I had to thrash the nuts off it, consequently I got no more than 40mpg. I could have got more and had a far better driving experience with a diesel.

the diesel doing short trips kills them is b*lox IMO, we have run 1.4 & 1.6 tdci fiestas on short trips for years and they have been fine.

BUT… could be different for ‘fancier’ diesels.

How short monkeyboy?

Newer diesels with DPF’s fitted are the one’s affected by short journeys.
Generally most can cope with lowish (40mph+) sustained speeds to regenerate the DPF, although I’ve heard some need 2500rpm+ for 10-15 minutes.
So long as the car has regular runs that include 5-10 mins of reasonable speeds, most cars can run the cleaning (regenerative) cycle to maintain the DPF. If not, then if you have the occasional longer journey, wind up the speed (or hold a lower gear) for recommended time period to enable required rpm’s for DPF cycle to occur.