Reliability vs Longevity

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Nov 3, 2002
Ok, time to stir the pot. Is it possible that reliability and longevity are mutually exclusive? Could it be that a car that is quite reliable might not also last the longest? Of course there are exceptions, but this might actually be true if you think about it. Not to answer my own question, but reliability pertains to the engine, longevity pertains to the body. Take a car like a Geo Metro, or a Nissan Sentra. They might be reliable, but are not the first car I'd think of for super-long lifespan. On the other hand, a glitchy Saab or old Mercedes might be a pita, but tend to last a long time. I just want to draw out the issue, because sometimes the difference between reliability and longevity is often missed.
anything out there-no matter the brand- is good for at least 150/200thou miles with few problems as long as it is maintained. And yes this is to include Geo Metro's(of which I have run 2 well over 200thou each so far and am at 112thou on another-ala Swift- as of today) So much of running something this long has to do with just keeping it, for the most part people get tired of their rides and get rid of them before their time-especialy little uncomfortabe little cracker box cars like these- when people can aford something nicer they move up. But with Metro's and Sentra's and these +++$$gas times, I don't think you will not be seeing too many of these for sale in to many places for the people that own them will be doing just what you are speaking of here. I think we are going to be seeing their 'longevity' being exstended pass the bordom point of owning them like never before! Try to find a Metro for sale right now-none to be found in this area except for the ++100000++miles ones maybe that are pass the point of no repair.
Um, what's wrong with something like an old Caprice or Crown Vic? My 1992 Buick Roadmaster has just under 290,000 miles on it, it's all original, and has been as reliable as a stone axe. The only things ever done to it other than regular items like plugs/wires/cap/brakes/etc... and oil changes:

- lost alternator at 220,000. Replaced with only thing available at the time, a cheap *** Bosch.
- lost alternator again at 260,000. This time replaced with an AC/Delco (yay!)
- transmission lost overdrive at 240,000. Fixed.
- ign. module in cap replaced 30,000 miles after it was due.
- did intake manifold at 275,000

I think that's been it. Oh yeah, tires.

Mobil-1 almost it's entire life, every 3-4000 miles on average. Trani. drop and refill (and filter, duh) every 30K approx.

That car started in the coldest weather, ran like a top, would smoke the rear tires and get 18-20 mpg all day long. On the road I'd get 25 and making 300ft-lbs of torque at 2200 is nothing to sneeze at, although to get the full 180hp you had to wind it way up.

Status: sold to my dad.
If reliability applies only to the engine for your example, then I think the Swedes are certainly front-runners. However I have to go with small-block Americans along with them.

To directly answer your first question, though: Most any sentence that begins with "Is it possible..." must of necessity be answered yes, including this one: "Is it possible the sun just went supernova and in a few moments we're all going to be vaporized?" Yes, it is possible, statistically speaking. As a practical matter, no it is not possible. So, the answer to your first question about reliability and longevity being mutually exclusive is, as a practical matter, definitely not. The answer to your second about whether the two items might not be present in any given vehicle is of course yes.

As to the draw things out part, I say go fish. The simple fact is that European cars, overall, are more expensive to buy, more expensive and more time consuming to maintain, and may or may not live longer when you spend all those extra dollars on them. The same was still true of Japanese nameplates at least as of a few years ago. This has been shown again and again empirically. I would gladly point you to a convenient URL if I had one here, but if you truly are interested you'll find hard data by searching. If you just want your favorite brand to "win," good luck with that. I have found some models of VW and Audi to be very entertaining to drive. Empirically, they are not very reliable, nor do they have spectacular longevity, and they are more expensive in the mean time. If the fun is worth it to you, more power to you. I have no problem with that at all. That's why there is more than just one make of car out there. Just don't try to tell me that "I like" = "is better."
Technically speaking they are 2 separate matters. Brianl703 has pretty much defined it for you, let me add that reliability is conformance to the original specifications without external means other than normal maintenance, while longevity implies (or at least allows) ongoing repairs.

Longevity also implies a cost/benefit calculation that is very subjective by each owner, whereas reliability is pretty much objective.

I can throw tons of $$ at a piece of junk and it will be a long-lived piece of junk. However, no amount of money will make an unreliable car reliable.
Yup, I've made the same distinction in other threads. An 87 Honda Civic that we had was fairly reliable compared to either the 93 or 99 Taurus that we have, but proved not to be durable as it was shot at 120k miles. The 93 Taurus has evolved in a higher life form, having made a slave of it's human owner :^), but it still runs at 190k miles.

VW bugs aren't reliable but they are very fixable and can last a long time, like many other older vehicles. The wiring harnesses, sensors, and actuators on modern fuel injected vehicles start being a real pain to deal with as they age, in part because there are so many of them. Add the typical electrical doo-dads that people have to have on their cars these days, the additional set of sensors, etc. on automatic transmissions to the ones on the engine, and you have a real rat's nest down the road. It'd be ok the diagnostics kept pace, but a lot of shops don't seem to know how to troubleshoot unless a code 'tells them what part to replace'.
Audi Junkie,

My guess is that you are trying to justify owning a German car by some rational, rather than emotional, means. I own a BMW. Lets face it, we own them because we enjoy the driving experience, not for practical reasons. A Toyota or even a Buick, is more reliable by any objective measure. Longevity is better among some luxury makes mainly because they have enough resale value to justify repairs, rather than scrappage, out to a longer mileage. A BMW, Mercedes or Lexus straight six engine may last 300,000 miles, but the rest of the car will not. I would not trust my 1992 BMW to set out on a transcontinental trip, yet for driving within the 100 mile AAA-Plus towing radius, I am perfectly confident.

Now you may have a point if you are comparing to a car, like a Taurus, that may have no problems during the warranty period, earning it a high reliability rating, only to have a blown transmission and head gaskets at 75,000 miles or so, about the time the value of the car has already sunk to about the cost of repairs.
How likely is it, though, that a car with long-term reliability problems (of the sort that take 75,000 miles or more to show up) will show fewer-than-average problems during the warranty period?

It seems to me that the sort of quality control/engineering problems that would result in the long-term reliability problems would also result in warranty-period problems as well.

Also, JD Power does not (correct me if I'm wrong) limit the 3-year vehicle dependability study to in-warranty problems, so repairs to a vehicle that's less than 3 years old but passed 36K are still counted.
Not trying to justify anything. Some of my cars cost nothing and run forever, and some cost a mint. I'm simply trying to look at a set of issues that tend to be lumped together. The most analytical point is that more expensive cars justify more expensive...and ongoing repairs. However, I don't see Cadilliac and Lincons making the cut as super-long-lasting cars, with the advantage going to Cadilliac...over almost ALL GM cars. Anyway, I go to the super-scrapper junkyard here,(Harry's) and as you walk from the domestic to the Asian to the Euro car sections, the cars get older. Maybe average US is >1994, Asian <1992 and Euro, well they are QUITE old...maybe 1985-87. Remember, not all Euro cars are expensive. Maybe the owners have more skills or just care more or whatever. Discuss.
"It seems to me that the sort of quality control/engineering problems that would result in the long-term reliability problems would also result in warranty-period problems as well."

statistically speaking that's exactly what happens.
My V6 Accord lasted over 500,000 miles, my 1.8L Mazda Protege' ran for 160,000 trouble free miles before I sold it, my MB 240D with OM 616 too gave me superb service, I still use a vehicle with OM 616 turbo, in fact the best engines from MB were the all iron OM 616/617 series, apart from that, no other MB engines till date have exhibited that much durability.

Originally posted by Gurkha:
My V6 Accord lasted over 500,000 miles,


In India? What were the road conditions like and how much chassis maintenance did you have to do?

How solid did the cars structure feel after 500,000 miles?

What finally caused you to get rid of the car?
I have to agree. I think longevity has more to do with love of car/money spent maintaining & servicing.
I think part of longetivity is whether the vehicle can be easily diagnosed and repaired should it develop a problem (with the assumption that the alternative to fixing the problem is to sent it to the junkyard) Some factors that affect that are:

1)Cost and availability of replacement parts

2)Ease of replacing parts that are most likely to fail

3)Ease of diagnosis to identify failed parts. (ie, spending 6 hours to track down a failed fuel injection component because the PCM has limited diagnostic capability..and this might well be required due to emissions test requirements).

4)Related to #3, the size of the knowledgebase about the vehicle. Is there a forum with 10,000+ posts about all aspects of the vehicle, which can be used to help diagnose a problem? Or has almost nobody ever heard of it, and those who have, want to forget it?
brianl703, I agree 100% with your first post. Also how much a model or powertrain changes over the years affects mechanics' knowledge thereof and availability of parts from different year cars (junkyards) and rebuilders/ 3rd parties. They need a certain critical mass to make reverse-engineering an OE part worthwhile. More/ cheaper parts options mean a longer time before a car is too expensive to keep. Also a design flaw has more chance of being noticed and corrected for improved reliability over stock.

Example 1: We all know a GM 60-degree V6 can have intake manifold problems. This even trends across different years and displacements of the same basic design.

Example 2: Saturns (my current favorite) have kept the same basic chassis dimensions, bolt patterns, etc., across the dozen years the s-series was made. They've always been speed-density, coil-pack-ignition 1.9 liter engines with two different heads for two different power outputs.

And, for most/all of the 90's, their dealership techs only had one model to work on... so maybe they got good at it!
Pre-1989,90 watercooled VWs were reliable and long lived. Then came Motronic and production too far away from the Fatherland for close supervision.

I won't say they suck, now, because that might start another VW-Hater thread (locking).

Originally posted by brianl703:
How likely is it, though, that a car with long-term reliability problems (of the sort that take 75,000 miles or more to show up) will show fewer-than-average problems during the warranty period?

It seems to me that the sort of quality control/engineering problems that would result in the long-term reliability problems would also result in warranty-period problems as well.

You have excellent quality control, that is, very repeatable production processes and a weak design. Design engineering and quality control are not the same organizations within a large manufacturing company.
Brian 703 lays out the technical argument, but I think you're all missing the real issue behind longevity/replacement of a car.....psychology/ego.

Just take a look at what they're still driving in Cuba... '55 Chevy's etc. It's because they can't GET anything else.

I've thought about this alot, and I think that we grow tired of cars long before they cease to be useful transportation. We either grow tired of them, or they don't give us that certain feeling when we're driving them, or we just have to have that shiny new "Canyonero".

If we were just buying cars for basic transportation, we'd all be driving base corolla's or some other base vehicle that performs the transportation function we require.

Of course "reliability" otherwise known as no trips to the dealership for repairs for a few more years is some added value of a new car. However, with regular maintenance, I believe that a 10 year old car of any mileage would give you pretty low odds of stranding you on the highway. Most problems on a well maintained vehicle raise warning flags long before they strand you.

Meanwhile, I bought a new car for me and one for my wife in the last 2 years....basically, because they're shiny and make me feel good.

Just my rambling two cents.

Originally posted by Jimbo:
You have excellent quality control, that is, very repeatable production processes and a weak design.

Wouldn't weak design manifest itself as in-warranty failures as well as out-of-warranty failures?
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