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having read it again I think your right stuartli, 180K does not seem many miles for a modern engine - especially in a work horse pick up truck.
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depending on serviceing and driver awareness im sure even the most humblest engine these days could easily achieve 200,000 miles (rovers excepted)
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With modern manufacturing techniques, engines must come off the line as identical as it is possible to get with the odd rogue excepted. I would think that a sympathetic driving style and sticking to regular maintenance schedules, oil changes in particular, must be worth 100, 000 miles over a carelessly used one where the servicing has been hit and miss.
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>>I would think that a sympathetic driving style and sticking to regular maintenance schedules, oil >>changes in particular, must be worth 100, 000 miles over a carelessly used one where the >>servicing has been hit and miss.
Pretty academic, I should have thought. Most modern cars 'die' (are deaded) because the ABS stops working and people don't know to wire the light up with the ignition light. Or because the exhaust needs a new cat. Or because the suspension bushes need changing. Or a new coil pack. (Sit back and wait for flames...), or the cam belt goes - or even the cam belt needs changing.
None of those is the *fault* of the engine; they're all servicing items.
So whether good servicing will make an engine do 500,000 rather than 600,000 is pretty academic.
Some cars are still around that will rust around the engine: Renault 21, W123 MB, (any Alfa where's ND these days, those jokes aren't funny any more), but generally because the car has been kept going for in excess of its design life.
And then there are Rover engines that fall out of rusted Rover hulks.
jimvho
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And then, going back to OP's point about a 180k 'design life'. What does 180k represent?
Is this an average - 50% of buyers will be unhappy?
A minimum?
Or the sort of advertising blurb that means anybody buying it new can have a nice warm feeling that he can keep it for 10 years and 150k and still there will be a market for it.
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depending on serviceing and driver awareness im sure even the most humblest engine these days could easily achieve 200,000 miles (rovers excepted)
I driven a 1.4 K-series with 240k and a 825 diesel with 300k, so dont think Rovers can be excepted - more like Mondeo diesels on reading on of the posts here!!
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Isnt there a Citroen C5 HDI around somewhere with over 400K miles on the clock?
Seen many a Peugeot XUD diesel with over 200K miles on the clock, Also seen a few XU petrol lumps with over 160K miles on them.
Also seen a previous shape Micra with a ruined engine with less then 40K miles on it because it wasnt ever looked after or serviced.
If you look after a engine correctly it will go on to give many years of service, even a K series.
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>>So whether good servicing will make an engine do 500,000 rather than 600,000 is pretty academic.<<
I agree with you (15 year old car with 150K on the clock is not worth repairing if the ABS pump goes) but do you think the designers think about engine longevity when designing the engine - and if so how long ?
I'm just curious by the way.
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There is a lot of rubbish talked about this.
Cars are owned by individuals thattreat them is a very different way.
This year i sold my VW camper of 20years old with 175K miles at a very good price ( new engine at 100K) body great.
I also sold my 15 year old Escort for a low price 112K miles- no new engine parts at all, so you can make a vehile last- I do . Look after them , including the bodies.
Fords rustmore than VW , but cost a lot more- you get hat you pay for but you can make a Ford last , and beat their game.
The latest Ford has 12 year body warranty but most owners will want the latest gimmicks well before then.
It is obsolescence that ruins car values. When you buy a new model the next is one the 'drawing board', you cannot win, so don't try.
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I dont know about cars, but vans generally do huge mileages so I would imagine that it is a consideration when they are designed - my neighbour puts 120k a year on his Merc vans and one of his is now 5 years old - still goes well, good for a ton apparently.
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Cars only die because they reach an age where they're worth so little that as soon as they change hands they tend to be neglected.
Buy a car for a grand, a lot of folks will run into the ground. Buy it at £500, and they're almost certain to.
So your 80K, 8 year old well-kept Micra becomes the same as the neglected new one above.
Look after a car and modern engines will last almost indefinitely. In the USA, where depreciation is slower, even cheap cars last 15 years/150K on average (official figures) so many of them will be lasting an awful lot longer than that.
Rust is barely an issue any more, engine life is huge, and even the suspension and electrics should last a good long while if looked after. The remaining factor is user neglect.
It's the sole and simple reason why a VW is "perceived" to last longer than say a Proton. The Proton hits banger money at 5 years old, the VW at closer to 10. Is it any wonder then that at 9 years old the Proton is falling apart? Most have been neglected half their lives. The VW will last say 13 or 14 years. Coincidence? I don't think so.
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Having spent a working lifetime in automotive development I can assure you that cars (and everything else for that matter) are not designed to last a particular length of time. They are designed as to be as durable as possible within the limits of current technology and the financial constraints of what their customers will pay. Manufacturers are constantly striving to make their products ever more durable. You only have to look at how durability has improved over the years. For example in the 1930s the life of an engine was 30k. Fortunately people didn't do the high annual mileages that they do now. Bodywork in those days was reasonably durable but this was only because cars had a separate chassis and the practice of putting salt on the roads in winter hadn't been thought of. When chassis-less construction and road salt came together cars corroded rapidly. When this became apparent it was countered by aftermarket underseal, factory applied underseal, more attention to not having water/mud traps, galvanising of body panels etc. etc. The durability of engines, transmission, tyres, brakes, steering and suspension etc has improved in leaps and bounds. To anyone who says "They don't make cars like they used to." my reply is always "Thank goodness for that."
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L\'escargot.
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High mileage capability is not the preserve of new engines though. I had a Y reg Sierra 1.6 with the 60's designed Pinto engine. That did 235,000 miles on its original engine which died eventually through a combination of neglect and oil pump failure.
I bought it a few months before its tenth birthday with 115,000 on the clock, and took it up to 195,000 miles. At this point it didn't knock or rattle, the cylinder compressions were still within new spec, and it used about half a litre of oil between services. I serviced it every 6k without fail, using Ford's own brand oil and a genuine Motorcraft filter, and had to replace a clutch, an ignition coil and a water pump.
Sold it to a mate in 1998 who needed a cheap runabout and he put another 40k on it, but as I understand it, never serviced it in that time. It rattled on gamely until 235k and then the oil pump failed and it seized solid. It is logical to assume that if he'd kept it serviced, it would have comfortably exceeded the 250k mark.
I personally know of a dozen or so "bread and butter" cars with between 120k and 200k on that are still utterly reliable and in day to day use. These include a couple of Mondeos (mine included), a Golf, a Focus, a Vectra, a Rover 416i (Honda lump), a Renault Espace and a Subaru Impreza Turbo.
Cheers
DP
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>>Cars only die because they reach an age where they're worth so little that as soon as they change hands they tend to be neglected>>
That is true and is why older cars in Scandinavia are better condition than here, they are worth more as a result of higher new car prices and therefore are looked after better as they age.
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Engine longevity has been increasing steadily since the end of WW2 but given an element of randomness, different driving styles and different maintenance care it's impossible to give a figure for a particular engine as one example might get double the life of another.
The GM SOHC engine in our old Nova, designed in the '80s, got to 126k with no more than scheduled maintenance before a reconditioned head was considered uneconomic. With better care (blame today's youth) it would have lasted much longer.
I'll be shocked if the more modern GM 16v Ecotec, we now have, needs anything other than scheduled maintenance before 150k and disappointed if we don't get to 200k.
I'm sure there are more expensive cars with better engine longevity but I perceive that mass market makes like Vauxhall and Ford have improved much more, proportionally, than the quality brands and that the gap between mass market and quality brands is much less than it used to be.
But anyway, does it matter? The average life of a car is still 14 years / 120k as it has been for decades!
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I think L'escargot is right with regard to cars.
An engineer once explained to me the difference between designing a car engine and one for an aeroplane. In a plane, weight is absolutely crucial, so every single component is designed with a known working life in mind, measured in hours running time. As that time approaches, metal fatigue starts to become a risk. So the pistons will have a "replace by" period of so many hours, con rods, oil pump gears, flaps, doors, chassis members, the whole lot. Everything has to be logged and meticulously scheduled for replacement at the due time.
Cars on the otherhand are ludicrously over-engineered. Everything is virtually built for life. You cannot look at a 5 year old crankshaft and measure how much metal fatigue it has suffered so therefore calculate its remaining life. Given proper oil changes, filters, and useage it will last forever. No car manufacturer would design it for a 200,000 mile life, and then specify that it must be changed every 100,000 miles to be on the safe side.
The same with body components. A car door could be designed to suffer fatigue at 200,000 miles. It would probably be a lot lighter. But it wouldn't be worth the expensive design work involved, and no one would be prepared to buy a car that was designed to fall apart. In an aeroplane, everything is designed to fail, but predictably.
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Another way to say virtually the same as Cliff's post is that during design and development of a car, any load bearing part found with a crack is deemed to have failed. This also applies during the service life of a car - I certainly wouldn't be happy with mechanics deciding whether a crack is acceptable or not. That MOTs are carried out by people with no training in the analysis of structures is not ideal! (but I wouldn't argue for a more stringent or expensive MOT)
In a practical sense, parts are designed and developed, and if they pass the development tests, they are OK. So, any difference between manufacturers is not only in their design rules, but also in their development test specifications and procedures.
With aicraft, (and many other engineered structures), finding a crack is only one part of the fatigue management of the structure. Typically, the types of structure this applies to are those where the cost of manging fatigue is much lower than the cost of replacement of the structure. Cliff is right to point out that many aircraft parts are "lifed", which is in effect one fatigue management option, which is attractive for small, easily replaced parts. A crack in a wing spar would be managed quite differently!, and one possibility is to continue use of the aircraft, while monitoring the growth of the crack periodically.
For aircraft, the specification of development tests is still quite manufacturer specific, but there is the extra burden of flight qualification tests which are referenced back to national and international standards, and hence much less variable.
For some structures, where detailed inspection is difficult, or impossible (some parts of oilrigs and nuclear installations), one approach is to assess the structure based on the supposed existence of a crack which is just to small to be seen using the coarse inspections methods available (say if you can feasibly inspect to 5mm resolution, but no finer, you would assume a 5mm crack is actually there, positioned and aligned in the worst possible way with respect to the prevailing stress state of the material)
Number_Cruncher
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