Reliability on newer turbo diesels

[Mr_Sukebe]

A thread on an alternative forum made me wonder about the newer turbo diesels.
In summary, the chap (sounded like he was a technician/mechanic and seemed to know his stuff) was suggesting that the tolerences on newer TDs are much finer than they used to be and the side effect has been a significant decrease in their reliability.
An example being the newer 2ltr BMW TDs which are far more stressed than the older units and from reports appear to suffer a lot more turbo failures than they used to.

Linked to the above. If you are running up mileages of say 15k/year then you're probably looking at a saving of say £1k/year in fuel when comparing a 320i to a 320d. How much does a turbo replacement cost for a 320D? If it's say £1k or less, you can have a turbo failure every year and it would still pay for itself.

Thoughts?

Update: initial comments elsewhere on the net suggest that the repair costs are in the region of £2400. I wonder what the stats are on failure rates.

 

[<(Multi)>]

Myself and my work mate have Golf TDI's. Mine racked up 48k before it blow its engine, turbo and Cat. My mates' which now has 78k on the clock, blow its turbo and cat last week. These cars arent old, they're both 56 plates. Personally I wouldnt buy a VAG car after this, the service from VW was aweful too.

 

[Bill101]

Finer tolerances means a better fit ,so I don't see how it would lead to more failure unless it was really abused during it's early life. I remember my old Golf TD went better after around 88k.

 

[233]

hmm

cant complain about any of our vag dervs,

have a number of them well over 100-150k miles and still going strong,

nothing that wouldnt be attributed to normal wear and tear.

 

[GeX]

modern diesels are more powerful, yet similar sizes. so more stressed, they are not as tollerant to poor servicing, poor fuel etc as they would've been before. makes sense they're not as reliable as they once were.

 

[therealnerd2]

Finer tolerances means a better fit ,so I don't see how it would lead to more failure unless it was really abused during it's early life. I remember my old Golf TD went better after around 88k.

He means i different sort of 'finer tolerances'. Finer tolerances as in performance specification, economy specification, i.e. less engine flexibility so they leave tolerated range more, so less reliability

 

[Stonedofmoo]

It's what you get for greater fuel economy and performance. No different to petrol engines really

Engines like the one in my 306 are old workhorses and practically live on forever. But they are unrefined, the power comes in lumps and the economy is about 8mpg lower than it's modern day counterpart.

 

[GeX]

Engines like the one in my 306 are old workhorses and practically live on forever. But they are unrefined, the power comes in lumps and the economy is about 8mpg lower than it's modern day counterpart.

but given the chance, it'll run on its own engine oil

 

[Stonedofmoo]

Yeah pretty much

I actually much prefer the older turbo diesels as I like the surge of power you get, it makes you feel like you've actually got some power to play with. Modern diesels are far too refined and dull to drive imo.

 

[[TW]Fox]

Linked to the above. If you are running up mileages of say 15k/year then you're probably looking at a saving of say £1k/year in fuel when comparing a 320i to a 320d. How much does a turbo replacement cost for a 320D? If it's say £1k or less, you can have a turbo failure every year and it would still pay for itself

Except it wouldnt, as the diesel would be noticeably more expensive to buy in the first place.

15000 miles at 45mpg = £1634
15000 miles at 30mpg = £2360

So a saving of what.. £700.

 

[Mr_Sukebe]

Except it wouldnt, as the diesel would be noticeably more expensive to buy in the first place.

15000 miles at 45mpg = £1634
15000 miles at 30mpg = £2360

So a saving of what.. £700.

It's all really a question of how long the car goes before blowing up, vs fuel savings. Even you were to save say £700 a year in fuel and the engine lasted say 4 years, that's £2800. So might pay for itself.

The additional cost of the car is debatable, as the actual cost to run is the depreciation plus opportunity cost of not using the dosh elsewhere. Chances are that there's not a huge amount in it.

 

[jaykay]

Not really about the turbo, but in the BMW 320d, their inlet manifold can go.
Its made out of plastic and over time is warps etc. When it finally goes, it can be ok, but most of the time the swill flaps get sucked into the engine, meaning total engine failure.
Not sure how much of the BMW diesel line up it effects. These are all from the E46 model.

 

[GeX]

It's all really a question of how long the car goes before blowing up, vs fuel savings. Even you were to save say £700 a year in fuel and the engine lasted say 4 years, that's £2800. So might pay for itself.

The additional cost of the car is debatable, as the actual cost to run is the depreciation plus opportunity cost of not using the dosh elsewhere. Chances are that there's not a huge amount in it.

using these figures, say it needed a £2800 repair after 4 years.. you've not come out the outside breaking even - you've been driving a diesel for 4 years

 

[Phal]

Modern Petrol engines dont suffer from failures?


Are we saying that petrol cars are more / equally / less reliable than diesel cars?


If its equally or less reliable then this thread is a bit lose tbh and if petrol cars are more reliable then where is this info coming from?


You could argue that a turbo failure is something more common to a diesel car since nearly all modern diesels have a turbo where as this isnt the case for petrol cars.

But then again you could also argue that you dont really want to do 50-100,000 miles in a non turbo petrol car unless youve got a decent size engine in it. Then youre either gonna be paying more for petrol or be at the same risks as a turbo diesel :\

 

[GeX]

course they do, but petrol engines don't have the same percieved reliability attached them that diesels do.

 

[Phal]

Well so far weve got accounts of 3-4 cars having problems from this thread? Hardly concrete proof of dropping reliability standards lol


But yes, I expect that as the push for more and more performance from smaller diesel engines progresses, reliability will drop :/ but then again thats just life.


Guess thats why everyone talking about those big yank engines is always harping on about how reliable they are and that theyll run forever the more power you squeeze out of something, the more likely it is to fair! Where as those huge engines running at low states of tune will be under a lot less stress and therefore will be likely last longer.

 

[Snaggle]

Work mates octavia on a 56 plate just lunched its turbo/engine/cat with about 60k on it . I have the same car and its been fine but so was his till a week ago .. Although i have had diesel cars for the last 10+ years and never had an issue .

Persil

 

[Tinders]

Bear in mind a lot of new TD's are purchased by company car drivers, they aint exactly well treated, they may be serviced on the dot, but that doesnt really stop the car from being used and abused badly!

 

[Gaygle]

Myself and my work mate have Golf TDI's. Mine racked up 48k before it blow its engine, turbo and Cat. My mates' which now has 78k on the clock, blow its turbo and cat last week. These cars arent old, they're both 56 plates. Personally I wouldnt buy a VAG car after this, the service from VW was aweful too.

Admittedly the car did nearly 80,000 miles in under a year?

 

[NickXX]

However the turbo won't blow every 15,000 miles, don't know what the average is for a 320d but I would expect it to be close to 100,000 miles.

If of course you buy an old 320d and run it for only a year suffering a turbo failure during that time, then you're stuffed.

That said, I've managed to blow a turbo on a Golf TDI with 10,000 miles on the clock, whereas my 330d has managed 126,000 on the original.