Should Our Next Car Be Petrol or Diesel?
As you might know, we've got another baby on the way chez Howlett. This will bring the head count to six. Hence we won't all fit in a standard 5-seater car and we're now looking for something bigger. A seven-seater.
We've all but made our minds up on a Nissan Qashqai+2 and this week we're probably going to order a new one. When I say new, I mean new. As in built to order. Although I swore I'd never do that again after I bought a brand new Golf GTI back in my reckless twenties, which ended up just being nothing more than a fancy lease car and a waste of money.
For various reasons we're going to be able to buy a brand new Nissan Qashqai for less than it would cost to buy any other 7 seater from the second hand market. Although I should point out that Karen refuses to buy a "people carrier", so we're restricted to the "crossover" variety of SUVs.
Anyway. What I can't decide is whether to buy a petrol or a diesel model? Everybody says buy diesel as they're cheaper to run but is it as clear-cut as that?
The diesel models are a grand or more expensive than the petrols. How much mileage do you have to be doing to start getting a return on this? On average we spend about 150 pounds a month on petrol.
Another issue is that the salesman (admittedly a slime-ball) advised us against a diesel, based on what we'd told him of our driving habits, as the diesel Qashqai has a "FAP" filter on the exhaust and unless you travel at 50mph for about 30 minutes at least once a week it will clog up and be expensive to clean out, thus negating the cost savings of a diesel.
Any thoughts? Just how much more economic is a diesel?
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If most of your driving is about town then I don't see the benefit of getting the diesel. If however most of the driving is on Motorways, then you'll see a saving in the fuel costs. Cruising at speed is far more economic in a diesel. Just my observations.
I get approx 47 mpg from a Ford Focus (6 years old) with mix of town and country A roads driving. Average speed over 500 miles of 30mph on my standard commute. The mpg always shoots up when on motorway journeys.
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Should have said, my Focus is diesel.
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500 mile commute Jon?
We went to Northumberland and back this weekend but in general don't do much motorway driving at all. General use is about town and from one town to another (Nottingham to Mansfield is a popular one and that's only 14 miles each way).
Karen commutes to work two days a week (about 10 miles away). I don't use the car for commuting at all and very rarely for business meetings (couple of times a years perhaps).
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When we bought our diesel Astra we were told the break even point was about 24000 miles which I roughly do in a year. On the motorway the Diesel seems more economic than our Mazda 6 (Petrol).
Based on what you say the petrol would be the way to go....
Top Gear are not too complimentary about the Nissan, not much room for luggage which leads to roof box and poor economy. Some of the mums at our school use VW's Tourans (which I like) and larger like the Sharon.
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I though the Top Gear review of the Qashqai wasn't too bad all in all. Do you mean the online one? http://www.topgear.com/uk/nissan/qashqai
The trouble is that Karen is all about appearance. A Touran is too much like a Renault Megane kind of people carrier which Karen wouldn't be seen dead in. She's a very difficult lady to please and practicality isn't a major consideration for her.
Jake
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As Jon said ...
It depends on how much you'll drive in a year. In Germany the calculation is rather simple right now. If you are driving approx 25.000 km a year and you are more on the side of getting the engine warm when driving you should right now buy a diesel.
Which is also what your salesman said when he heard about your driving habits.
And yes the FAP system needs the catalyc converter to be hot to burn the remainders from time to time. It was developed by Peugeot 10 years ago and nothing i ever read or heard about it implies that it needs to have a certain speed or duration of driving ...
http://en.wikipedia.org/wiki/Diesel_particulate_filter. The german article is far longer and has a better description.
We have a T5 Multivan 2.5 TDI for our family which consists of 2 + 4 kids = 6 persons + a dog and you see a difference of 2 litres/100 kilometers if we are driving him mostly cold or getting him warm.
If not it is a petrol.
Another advantage of petrol i have seen rising for the last years is that you can easily convert the engine to be a LPG or CNG burner with not too much of a hassle. This leads, at last in Germany to roundabout halfening your costs for fuelling.
A simple, purely cost oriented calculation would be ...
Buying price + (((liters per 100 miles * cost per liter * (miles per year/100)) + insurance per year + maintanance per year + tax per year) * years of usage) - selling price after n years of usage
... calculated for both car engine types.
With that you will have nearly the real costs of your car. If you want to have the real costs you must also include tires and oil and interest (if you cannot pay cash).
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Trust a German to have an equation ;o)
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As a general rule you would probably find that you use approx 30% less fuel using Diesel over Petrol for the same size engine.
You then have to take into account the difference in price between the 2 fuel types. At this moment in time there isn't much difference, however about 12 months back it was approx 10-15p per litre more expensive.
For your estimated mileage based on 150 Litres of fuel a month, I personally would go for the Petrol version.
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Do you have two vehicles? If so go for what ever fuel the other car uses. We use to have one of each, and someone (me), filled up the diesel car with petrol on the morning we were driving down to Dover to get the ferry. Suffice to say I was not popular........
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We'll only have the one car Phil. Although Karen has only ever had petrols and had already expressed concern that she might do as you did.
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I bought my first diesel this year and will not go back to Petrol. The new diesels have extremely low emissions and therefore lower cost road tax. The engines tend to me more resilient (its quite common for diesel engines to still be going strong at 200,000miles) therefore limiting the depreciation on resale value - all this before you even start thinking about fuel costs/economy.
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That's a very good point typically diesels have better residuals than petrol, tougher and for my money safer engines too.
I once drove a turbo diesel Transit home from Devon when a fuel pipe above the engine broke and leaked diesel onto the top of the engine. The fumes made me pull over to find a puddle of fuel sitting on top and not hint of fire. If I'd been in a petrol car I'd have been a bit crispy.
OK it doesn't happy everyday but I'm sticking with my diesel SRi :-)
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Ditto on the engine life. I just bought a used 1994 Ford E350 U Haul truck with 197,000 miles and the engine is still running great. Diesel engines have fewer parts so less to break and no plugs so less electronics to mess with. I'm not sure on the fuel efficiency; we haven't gone through our first tank yet, but I didn't buy the truck to save money on fuel.
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I would take the "filter clogging" issue seriously. Over here (Belgium, a diesel country) there were some stories in the news where people bought new diesels (with filter), "like everyone else" (because of the cheaper fuel + better mileage) but with driving habits that didn't warrant a diesel. Turns out they regularly need to pay for a filter cleaning.
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I'd say get a diesel just because it's a diesel. :P Loads of power, and the engines are more reliable.
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The german ADAC (Motor Club) have calculated what is cheaper, petrol or diesel for 1015 diffrent car models.
A summary with the "top ten" cars can be found under http://www1.adac.de/images/b-d-vgl-auszug_tcm8-131259.pdf . As a Meber of the ADAC you can access all results.
They calculate for 4 Years, including depreciation (without interest), oil change, service, typical wear parts, costs for tyres, german car taxes, german comprehensive cover and the following fuel prices:
Diesel 1,10 €
Petrol 1,30 €
For the Qashqai+2 1.6 petrol and the Qashqai+2 1.5 diesel the differences per
10.000 KM -> Petrol 55.2 €-Cent/KM , Diesel 55.6 €-Cent/KM
15.000 KM -> Petrol 41.7 €-Cent/KM , Diesel 40.6 €-Cent/KM
20.000KM -> Petrol 35.4 €-Cent/KM , Diesel 34.1 €-Cent/KM
I send you a Mail with the Qashqai results.
HTH.
My brother is driving the Quashqai (Petrol), it is a nice car.
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Why not a gas Natural Gas or Liquified Petroleum Gas?
I'm not sure if Qashqai LPG is available also in UK, in Italy i have ear are available.
At Italian price LPG are 10% economic than Diesel and the CNG 25%, plus tax reduction and no traffic restriction.
If you want install an aftermarket LPG or CNG system you must request to the seller if this broke the Nissan Warranty, i.e. in italy VolksWagen mantain warranty if you install a Landi Renzo system.
Nissan/Reanult probably mantain warranty with B.R.C. system seem the one used for te retail versions.
Take a look at for information in Uk
http://www.whatgreencar.com/lpg.php
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As a poor American I don't get to feel the diesel love. Only VW and Mercedes have them available and in a limited supply.
Although I have been lucky to find two good ones. My second car ever was a 1987 Ford Escort 2.0 Liter... 45-50MPH. My other diesel was a 1983 300SD Mercedes.
I loved both cars and if Ford would sell a similar car now in the States I would jump all over it.
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Actually BMW has had a diesel engine available here (in the 335id and if I recall 535id) for several months now, and Audi has also recently (or is about to) brought one over.
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A few things about diesel:
1) Do you like the chug-chug sound of the engine? (noticable if the windows are open)
2) When filling up the tank, you get diesel smell on your hands (unless you wear gloves or something like that)
3) Slight lag in power kicking in ...
4) Usually have lower emission rate and may mean that your road tax is lower (if it is based on emission rate not engine capacity).
5) City driving, it is a bit of a glutton on fuel ...
6) Town to town driving, it sips the fuel ...
7) Lower maintenance (however, oil could be a bit more expensive than oil used for petrol engines)
Notes:
1) I drive a diesel.
2) re Qashai 2+ - are you sure you can fit 6+ people and their gear?
3) if you can, buy a 2nd hand one that is < 6 months old - someone else has taken the massive depeciation hit.
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"Another issue is that the salesman (admittedly a slime-ball) advised us against a diesel, based on what we'd told him of our driving habits, as the diesel Qashqai has a "FAP" filter on the exhaust and unless you travel at 50mph for about 30 minutes at least once a week it will clog up and be expensive to clean out, thus negating the cost savings of a diesel."
While this _might_ have been a problem prior to the 1990s (when high sulphur content diesel fuels began being phased out worldwide) due to the fact that diesels take longer to warm up than comparable gasoline engines; I suspect that this is actually nothing more than a horseshit lie being fed to you by a slimeball dealer in an attempt to close the sale as quickly as possible.
Gasoline engines are more complicated and (in the long run) will always be more costly to operate than comparable diesel engines. Diesels cost more up front, but they last longer, get better fuel mileage, and are require significantly less maintenance. If you keep the air filter clean, change the oil and fuel filters at the manufacturer recommended intervals, a modern diesel engine will easily last 200,000+ miles before an overhaul is needed.
And even though you're not getting a "truck" per se; my daughter's comment to her friend (when asked about why my truck was so loud) still holds true: "Real trucks rattle". ;-)
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Some interesting info on how a diesel engine works compared to gasoline engines. http://www.howstuffworks.com/diesel1.htm
I have to say - cost savings appear to be on the mark for a D fuel option. But you're going to easily burn a lot of savings in depreciation buying new, surely? Just off lease is a great option - typically low miles and the depreciation is already burned off. Our last two petrol burners (gasoline!!!) we bought just off least and saved $6k on the Dodge Minivan (family APC) and $11k on the Honda Accord I commute with. It has 171,000 miles on it now with regular maintenance (about $600 each year) and gets about 33 mpg (about 11.6 km/L).
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Jake,
Beeing a huge Diesel fan (we own two Diesels and a petrol car) i do want to point out the advantages of different engine types:
Diesel: Expensive to buy, has a larger weight. More fuel-economic than a gasoline car. Some people are scared of the exhaust fumes. Filters do a great job.
Advantages: higher torque (on TDI's) comforable and silent ride when on te motorway. Engine will last longer than a petrol engine.
Disadvantages: Not suitable for short drives (that's why we've got the petrol car, going to the mall and stuff)
Petrol:
Cheaper to buy, Less economic than a Diesel. Less chance to be banned from urban area's than a Diesel.
Advantages: Cheaper then a Diesel to buy, cheaper to maintain.
Disadvantages: Fuel consumption and price
Gas/LPG:
Same as the petrol car. But will not last over 120.000 km (because of the thermic loads on the engine, and the absence of fuel based lubrication)
Advantages: Cheap fuel
Disadvantages: just 70% of engine power available, not allowed in channel tunnel
Hybrid:
Hybrids are a hoax, better buy an economic Diesel. Stay away from them.
My advice would be a Audi Q5 (if the budget is there, just because it is a great car) or a Renault Espace. Beeing a huge fan of TDI's and Audi's my opinion is slightly biased ;-)
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Your comments about lpg engines is false.
Taxis in Australia run on LPG and last upwards
of 500,000km.
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The petrol/diesel cost will be neither here nor there (based on what you say about your driving). Highest cost of motoring - easily - is depreciation.
The most important factor however is to go with what your good lady prefers to drive and dont sweat it...
:-)
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What does your wife like driving best?
The most expensive thing about vehicle ownership is depreciation. If you bail out early due to lack of love of a vehicle you will get much harder than the other ancillary costs like fuel and type of engine.
Good luck.
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In the Netherlands, diesel starts to become interesting from 20,000 km and above. However, a key reason for this treshold is the higher purchase tax for new diesel cars, not its actual efficiency.
In terms of actual efficiency, I'm no expert. Still, my impression is that the new diesels are extremely efficient and the old acceleration problem is gone too. I do agree that diesels are made for longer drives. I also have the feeling that diesel engines are way more robust. I've driven diesels all my life and never had any problems related to the engine, not even for small cars with LOTS of mileage.
I think the key parameters to decide are:
- purchase tax of the car: is there a difference?
- diesel vs gas price
- your driving behavior
- how long you want to last with the car (sell half-way or drive till it dies?)
My (unpopular) advise is that cars are always a waste of money. Use some sense in how to minimize that waste. I think generally it is best to buy a new robust car, maintain it well, and drive it until it is no longer financially responsible.
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Here there is a cost comparison tool it is in italian and also in english french and german(can be you have to start from home page)
http://www.metanoauto.com/modules.php?name=Costi_Carburanti&pa=confronto
there is also an off line javascript version to calculate with your price.
@Anro i have sell mine old car at 200.000 Km some car on the site have worked for 400.000 Km. The most important thing was have a strong valve seat.
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Jake
I bought a new qashai n-tec this year, and had the same dilemma. I went for the 2.0 petrol in the end, mainly because
a) it was cheaper
b) my wife didn't really want a diesel
c) although they are much more quiet now, diesels still smell!
We get about 35mpg on average, and have been really happy with the car so far. If we did a lot of motorway miles I probably would have gone for the diesel as the mpg is much higher.
I used the parkers diesel calculator (http://www.parkers.co.uk/News/Motoring-Costs/Petrol-vs-Diesel-calculator) and worked out that based on our mileage it wasn't worth it. However, the residuals argument still rings true if you are only planning on keeping it until the warranty runs out.
Hopefully they are still doing the 0% finance deal, as that was another reason for buying a new one!
Ben
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I'm basing my opinion on my big Ford 7.3 liter diesel. Smaller motors may be different, but I imagine they're similar.
If a diesel doesn't get up to proper operating temps you'll start gumming up the works and get 'wet stacking'. Essentially the diesel starts building up on the valves like coats of varnish because it's not hot enough. Idling for extended times can cause this as well (i.e. stil not up to operating temps)
As far as the FAP filter (my old truck doesn't have one), I believe it works by simply catching diesel particulates and heating them till they burn up. If this works off of exhaust heat then I imagine the salesman is right in that it'll never be clean.
In short, for a diesel you drive it hard like you're mad at it. It pays you back by running better, and you'll still get good mileage. It's the choice if you put on a LOT of highway miles and plan on keeping it a long time.
If however you just take trips to the local store and turn it on and off many times during your routine, or you don't know what you want to be driving next year, go with the gas (or a hybrid?).
~E
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Don't want to confuse things or be over scientific. Like to keep things simple - especially when it comes to a car.
Go for diesel - if you want power and economy. I have a merc eclass - not a huge engine but it can still shift (0-62 in 8.1 secs). And if driven in a normal sort of manner you can get 40 - 45 mpg (and this is an automatic).
Only drawback is noise - inside the car it is non-existant - does sound a bit "taxi" like outside - then again I am not outside...
For the family it is safe and has plenty comfort. Does economy and performance.
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To minimise your fuel consumption buy the
FWD models not the AWD models.
Are you buying auto or manual?
I very much doubt you can fit 6 people plus
luggage/prams etc in a Qashqai (called a Dualis in Oz)
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