Diesels still cost more than petrols to service in my experience. An example, we have 2 Alfas, a 156GTA and a 147 JTD, both recently had their 24k mile services at local dealer. The GTA cost £220, the 147 £355!! (and the 156 takes 5.9l of rather expensive 10w60 oil).
I do think though that the 36k miles service will be less on the JTD, but how much so I dont know.
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I think that previous conclusions in the BR have been along the lines that you would be skating on thin ice looking for savings on a diesel at 15K miles per annum. At that sort of mileage you'd be better off with the petrol unless, like me, you actually prefer the diesel-driving experience - which you seem not to.
My experience is that diesel servicing is still more expensive, but we're talking £20 or £30 per service. Whether parts are more expensive is down to the specifics of the engine. For example, I had to pay a fortune for a starter motor on my old Isuzu Cavalier diesel (special geared thing - £500 job). But I should imagine you save elsewhere. My understanding is that modern diesels are very high tech and that can only mean bad news when servicing them later on.
Splodgeface
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This is a very good point. In my experience modern CR Diesel engines are economical, efficient and smooth - but cost an absolute fortune to fix if things go wrong. Moreover your average independent is unwilling to touch them because of the special knowledge and techniques required to work on them. This may change over time, of course.
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Aprilia, I agree with what you say but aren't petrol engines just as complicated these days? Haven't diesels just caught up?
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They certainly do cost a fortune to fix. The fuel system components in particular seem to be really expensive on modern diesels, the injectors and HP fuel pump especially are extortionately pricey due to the immense pressures they supply fuel at.
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In my experience - Mondeo TDCi 130 - major service (every 37500) £240 inc, minor (every 12500) £150 inc, both at main dealer.
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In my experience - Mondeo TDCi 130 - major service (every 37500) £240 inc, minor (every 12500) £150 inc, both at main dealer.
I think regular servicing will not be a great deal more than for a petrol engine. The problem comes when the car is out of warranty and has a fuel system fault......
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In my experience - Mondeo TDCi 130 - major service (every 37500) £240 inc, minor (every 12500) £150 inc, both at main dealer.
Your getting your leg lifted at those prices.
My Mondeo TDCi 130 37.5k service cost me £171 inc VAT last week at my local Ford main dealer, of which about £15 was an additional charge for adjusting the tracking. That was at my local Ford dealer - a 12.5k service is about £115. The labour content was about £56, but the service parts were discounted at 25% off parts counter list price so if I'd done it myself buying the genuine bits from the dealer I'd have only saved about £25. They also lent me a Fiesta for the day FOC. Hardly seems worth taking it anywhere else or the hassle of doing it myself.
Peoples Ford do them even cheaper - £110 for a 12.5k and £155 every 37.5k - this is the same charge for both Petrol and Diesel. The major services come out the same because the diesel fuel filter is £30+VAT, but the petrol needs spark plugs which cost roughly the same amount.
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Your getting your leg lifted at those prices.
Hi, Sounds like it pays to shop around, I know a local rural Ford dealer is less expensive that the one I have used lately however the fact that they are literally a two minute walk from where I work makes it very convenient, they will also give me car if i need it.
Where are you geographically?
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I'm from the North West. There is a lot of competition from Ford dealers round here - there are probably about 20 dealers within 20 miles of where I work.
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Aprilia, I agree with what you say but aren't petrol engines just as complicated these days? Haven't diesels just caught up?
Not really. The complexities of high-pressure Diesel injection are considerably greater than those of regular (i.e. indirect) petrol injection.
High pressure Diesels operate at 20,000psi+; the standard of engineering required is of 'aerospace' standard and the forces that the components are subjected to are quite enormous.
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Interesting, although my 156 JTD has a diesel filter at every service the cam belt change is 72,000 rather than the 36K of the petrol so I suspect it balances out. However the capital costs of the diesel is slightly greater with the fuel being 3-4p more expensive & I get 40.4MPG, I think given my drive I'd get circa 35-36MPG from a petrol so given the price difference I suspect the saving is minimal even over the 40K miles a year I do. Diesels aren't particularly economical driven hard and because 98% of my journey is mway I think that gives the poor overall economy. On a gentle run I get 43+mpg & on a really hard run get 36-37mpg.
And before someone leaps in and says my xyz diesel does 100mpg yes I know and they drive probably a lot more gently than I do. EG. Old Escort 1.8TD was 40mpg and dead slow......
Jim
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They are very realistic figures Jim. I always have a little giggle to myself when people come on here and proudly state that their trip computer was displaying 65.8 mpg on their latest 90mph motorway journey.Little do they know their computer is wildly inaccurate.
Diesels are economical when driven gently but the moment you get above 75 ish on the motorway economy really suffers.
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P - those figures may be realistic, but I don't believe a diesel 'suffers' above 75 any more than a petrol. This effect is mainly due to wind resistance, which has nothing to do with the fuel. My 306 handbook says 'fuel consumption can increase by 25% between 70 and 80 mph'. And yes, I do get 58mpg overall, mostly by doing 60-65 on the Mway; and no, my car doesn't calculate it, I do - over >10K miles.
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Only guessing, Andrew-T, but whilst the extra wind resistance will be the same regardless of engine type, if that extra effort pushes a diesel engine into a less efficient band then mpg could become relatively worse.
Just a thought. Not an expert.
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I think that could make a marginal difference, patently. But my handbook is not referring to either fuel - tho I suppose 'up to' could cover all sorts.
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"Diesels are economical when driven gently but the moment you get above 75 ish on the motorway economy really suffers."
Doesn't seem to make much difference to consumption in my wife's Xantia HDi (and we have had some long fastish trips on the continent in it). However, it does in my Berlingo HDi but I reckon that is definitely due to the brick like shape of the latter. Be interested to here the views of other diesel drivers on this - esp the likes of BMW diesels (except they wouldn't be tested much below 75!!) and (say) big 4x4s.
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If I still recall my lectures correctly (it was a looong time ago!) wind resistance is proportional to velocity raised to the 4th power. So big rise in wind resistance from 75-85mph.
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The aerodynamic drag force term in the road load equation is usually given as:
0.5 * rho *Cd * A * V^2
with rho being the air density, Cd being the much quoted drag coefficient, A being the frontal area of the car, and V being the velocity.
It is noteworthy that cars really should be compared using the product Cd * A, but manufacturers only ever quote Cd. Both Cd and A are properties of the car.
number_cruncher
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hence the name...
In other words, a doubling of velocity will lead to a quadrupling of drag...
Splodgeface
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Thanks - that really helps me understand why my Touran has a reasonable drag coefficient but far worse fuel economy than smaller vehicles
I found this on the www.globalcar.com/datasheet/Audi/2004AudiA4Avant2....m website
Touran 2.0 TDi
Drag coefficient: 0.31
Frontal area: 2.54
Cx: 0.79
Audi A4 2.0 TDi
Drag coefficient: 0.29
Frontal area: 2.14
Cx: 0.62
My Touran will just about get 40 mpg with high speed cruising whereas the A4 is probably at 50 mpg. The 22% difference in Cx factors says it all
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If I still recall my lectures correctly (it was a looong time ago!) wind resistance is proportional to velocity raised to the 4th power. So big rise in wind resistance from 75-85mph.
In theory however it depends on how the manufacturer manages the airflow around the car. Managed airflow can mean that the relative efficiency increases as the speed rises so the drag does not increase at the theortical rate. In aerodynamic terms airflow can be "dirty" at low velocities though clean up as the velocity of the air relative to the body over which it is passing increases.
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Per PhilWBe interested to here the views of other diesel drivers on this - esp the likes of BMW diesels (except they wouldn't be tested much below 75!!) and (say) big 4x4s.
OUr Xantia HDi (110) does around 44 whatever i throw at it. The only time it dipped was in the Alps, 40 celcius and Bourg d'Oisains to Alpe D'Huez daily for a week for the Luge D'Ete!
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Diesels are economical when driven gently but the moment you get above 75 ish on the motorway economy really suffers.
Disagree, my Mondeo TDCi achieves a measured 48mpg on 80-85mph (cruise control) motorway runs, the trip says approx 49mpg.
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Well, it seems that most people here do not experience a significant drop in economy at motorway speeds. My XUD 306 certainly seems to, but maybe the later CR diesels don't suffer as badly as older IDI engines.
Or maybe there is something wromg with mine...
I stand corrected!
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Because of the superior mpg, I save £10 to £20 every time I fill up my diesel beemer. I don't do a lot of miles but this feels like a real saving to me. Even if you only do 6000 miles a year, if you average say 35 in the diesel and say 25 in a petrol this is a saving of almost £300 which pays for a service.
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But you pay a premium when buying the diesel over a petrol unfortunately.Sometimes quite a large amount, and this can negate the better mpg.
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Disagree, my Mondeo TDCi achieves a measured 48mpg on 80-85mph (cruise control) motorway runs, the trip says approx 49mpg.
The gap between diesel and petrol seems very small on the Motorway - took my 2.0 16v Mondeo to Wales this weekend and on the way up recorded economy of 43.5mpg. This was with the cruise set to 75, and it was checked for accuracy when I refilled the tank when I got there - pretty much spot on.
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The gap between diesel and petrol seems very small on the Motorway - took my 2.0 16v Mondeo to Wales this weekend and on the way up recorded economy of 43.5mpg. This was with the cruise set to 75, and it was checked for accuracy when I refilled the tank when I got there - pretty much spot on.
Hi, I know a guy with a 2.0 Petrol Ghia X Mondeo, same model and year as my TDCi 130. He gets a good 44mpg at 70 (similar to you) though this plummets at higher speeds. However the TDCi does 55-60mpg at 70 on cruise and, as I said 48mpg at 80-85.
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To my mind this very noticeable increase in consumption between 70 and 80 (and presumably even more at 90) is a worthwhile reason for a 70 limit on the Mway. A lower limit was proposed during the 1970s fuel crisis, but can't remember whether it was implemented.
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There was a temporary reduction to 50mph during the '73 crisis. I think it lasted about two months.
I worked at the Bacofoil plant in North Woolwich at the time mixing printing inks. We used Ethyl Acetone and various other solvents such as the highly volatile one beginning with T which I can't remember how to spell. People were adding these to there fuel in various quantities of up to 50% to try and get round the shortage. Never heard of any immediate ill effects but some engines must have had their lives shortened as a result.
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