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Engine Reliability Data

Engine Reliability Data

(OP)
Does anybody know of a way for a consumer to gauge the endurance life of an engine before purchasing a vehicle equipped with it? My dream is to go to a vehicle dealership and be presented with data from unbiased endurance tests on an array of vehicles and their components. I want to know how many hours an engine is designed to last at a given duty cycle as well as the standard deviation in time before they fail on endurance tests. Instead, the salesperson tells me to "check out that sweet infotainment system" and then they fumble through a brochure before trying to convince me that I should get a crossover SUV.

The way that I have currently been gauging the engine's durability is by looking at generators that are equipped with the same engine that is in the vehicle that I'm considering. If I can't find a generator with the engine that a vehicle is equipped with, then I am far less likely to consider buying it (Toyota 1MZ-FE being an example of an exception).

That method doesn't work as well when vehicles like the 3.5L ecoboost come into question. I like the idea of a v6 turbocharged half-ton, but I also know that this platform is vulnerable to higher deviations from expected endurance.

Think about how many engineers there are in the U.S. Why are companies not marketing to engineers by giving them cold-hard data?

"Formal education is a weapon, whose effect depends on who holds it in his hands and at whom it is aimed." ~ Joseph Stalin

RE: Engine Reliability Data

That sort of information is highly proprietary.

Limiting your search to vehicles that only have their engines also used in generators severely limits your choices. It also doesn't consider other components that are equally mission-critical, but which aren't found in generators - like the transmission, suspension, brakes, etc.

In any case ... Is the engine really the limiting factor, most of the time? Most cars nowadays, in my part of the world, go to the scrap heap with functional engines but either rusted-out bodyshells, or with some other major component failure, or with an accumulation of smaller failures that would cost more to repair than the car is worth ... or, fully functional and not rusted out, but unwanted. Who wants a mint-condition Chevy Cavalier? The car gets traded in on a new one, but it's worthless even if it's all there and working.

On the vehicle-specific internet forums that I'm a member of, the most common causes of engine failures aren't "lifetime" related, but rather neglect or abuse related ... or failure to follow instructions in the operating or maintenance manuals.

I've taken a couple of cars past 400,000 km and the engine itself was still fine.

RE: Engine Reliability Data

It's easier than you think, look at the warranty.

You can rest assured that the warranty lengths offered are based on certain estimates made by the company with regard to how long they will last. There's a reason that VW powertrain warranties are 60,000 miles and not 80,000, for example.

As far as marketing to engineers- I've seen estimates that there's about 2.5 million of us out there. That's less that 1% of the population. Good marketing teams don't design campaigns that make 1% of the target market happy and alienate the other 99%.

RE: Engine Reliability Data

I don't know if they still do this, but long ago I've read about the 50,000 mile durability testing. Where teams of drivers went round and round a track at extreme speeds to put 50,000 miles on the odometer as quickly as possible - for a new design. So that's 50,000 miles of durability, but at very high speeds.

I presume that they must have stopped long enough to change the oil and tires once in a while.

In some case I recall that they might have set some speed records along the way (e.g. distance over 24 hours, etc.).


RE: Engine Reliability Data

I don't think you can read anything into the length of a warranty. A lot of newer, less respected companies give longer warranties to help with peoples apprehensions about buying their products. Does that mean they will actually last longer? Who knows? Most engines live many times longer than the warranties. If you want to have a good idea of an engines durability, look for something that has been around for a long time. Then there is plenty of real world experience. Nissan VQ, Chevy LS3 and lots of other engines practically last forever it you treat them right.

Marketing is never going to sell to Engineers, we ask too many questions and the marketeers don't know the answers.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Engine Reliability Data

"100,000 miles at 100 miles per hour" - was a Mercury promo for the then-new Comet back in 1964. https://www.youtube.com/watch?v=uz3JdH28N3I

This type of test run won't catch issues from cold starting, idling, etc.

RE: Engine Reliability Data

Consumer Reports is the only organization I know of that tries to compile and publish reliability data on any and all available vehicles in the US market. Of course, it is rearward looking, and may have certain biases built in, because of the consumer reporting methods used. But at least they make an attempt.

RE: Engine Reliability Data

There are car/truck related forums for every marque, and they are a wealth of information. Naturally, an owner is more likely to post his problems than to post that he has not had any problems. There are usually at least a couple dealer techs participating who see hundreds of cars a month, know the issues early, and also know the fixes. In the example of the EcoBoost'd F150's, there are probably 20 large forums for those.

RE: Engine Reliability Data

(OP)
I think consumer reports generally does a good job. There are some anomalies in their rankings, but for the most part it jives with what I've observed.

"Formal education is a weapon, whose effect depends on who holds it in his hands and at whom it is aimed." ~ Joseph Stalin

RE: Engine Reliability Data

Agree, engine durability is the least of worries. The mechanical powerplant will usually still be going when the luxo-infotainment-bling-electro-gubbins have all gone dark and/or fallen off or are NLA.

The "100,000 mile at 100 miles per hour" is the easiest kind of test. As most here know, wear takes place on cold starts and short trips. Once everything is at operating temperature, wear usually virtually ceases.

A bit OT, but vehicle owners, their expectations and their maintenance skills vary with the bell curve. I visit a variety of car/truck/hobby fora. The least technically aware are usually the luxury owners and Cadillac totally absolutely unconscious. Conversely, Ford Super Duty truck owners fora members tend to know granular detail of design, operation and maintenance. Those who participate in "squirrel car" fora tend to be at the extremes; either an engineer or a know-nothing-fan-boy.

Buying a used car tells much about how they're owned and used. There's no hope of finding a good used low miles Subaru. Those are typically run long and hard, repaired and run til there's nothing left. Conversely, used low miles meticulously maintained mint condition Porsche are dirt common. However, that's changing with Porsche SUVs; many are now everyday beaters and trust me, if you can't afford a new one, you can't afford a used Cayenne.

jack vines

RE: Engine Reliability Data

I enjoyed your post because it brings out some interesting discussion. I agree with most of the posts in that the information you seek will be available primarily as anecdotes. In fact, I will provide my own anecdote: I have a 2002 Honda Civic that I bought new as a commuter car. I have done minimal maintenance (change oil every 10k miles, brakes and tires when required, cam timing belt every 100k miles). Except the aforementioned, nothing gets serviced unless it fails. The car has 312,000 miles on the odometer. (For you metric guys, that is more than half a gigameter.) The engine runs great, but the car is falling apart around the engine. The CV joints have a lot of lash. The suspension groans and creaks. The body has a lot of southern california freeway rash. Fortunately, the original clutch still works fine, as I hate servicing clutches. Are there other cars that would do better? Maybe, but we also may be getting into details that involve a distribution of vehicle serviceability/reliability/durability traits that vary significantly within the same brand/model. (Based on day of assembly or distribution factors that we would just list as random.) I think the best you can do is reduce the risk of durability disappointment by purchasing a car that has a good (anecdotally based) reputation. If you do discover good statistical data, please inform all.

RE: Engine Reliability Data

If you truly want to buy the most reliable/defect free vehicle possible:

1) Don't EVER buy a car in the first year of production, or the first year after a facelift.

2) Don't EVER buy a car in the last year of production, or the last year before a facelift.

3) Don't EVER buy a car built in a factory that has retooled or relocated within the last year.

3) Try to buy a car built in the middle of the day on a Tuesday, Wednesday, or Thursday, if possible.

As far as engines go, discovering build date and time is harder, but less important because engine plants are more automated for critical tasks.

RE: Engine Reliability Data

how long a engine will stay fit for use will heavily depend on its actual use - and thus mileage will vary. on average smaller cars will now easily exceed 300.000 km with decent maintenance and larger cars may last longer. the fact that the same engine is used for other applications like generators is no indication of a long life expectancy. it merely shows that the engine manufacturer has found another outlet for his engines - and in most of alternative applications those engines are derated quite a bit to be able to support the more "industrial" type of use.

usually engines last longer then other parts of the car. most people change their car because they think it is no longer "fashionable", "too old looking", needs more repairs then they like or are afraid reliability will diminish in future or they can get a good trade in. whatever the reason to buy a different car, the end of life of the engine usually is not the reason.

warranty to a large extend is marketing driven. apart from legal requirements warranty periods are decided upon the view whether a longer warranty may lead to selling more cars in a given time frame or not - whereas the cost of the "warranty" should be borne by the individual mark up for each car. it is a statistical game - if you sell a lot of cars with a mark up of say $20 the total amount of money received will hopefully be sufficient to pay for the few occasions where warranty needs to be given. there is no such thing as a free lunch....

RE: Engine Reliability Data

I can tell you unequivocally that warranty periods are based partially (a big part) on empirical, methodically gathered test data generated over a period of years. I've been one of the people that gathers and interprets that data and makes recommendations.

Obviously there is a marketing component- but if it was based solely or mostly on marketing every car would have a million mile powertrain warranty.

Longer warranties sell more cars. It's not like there's some segment where a shorter warranty is appealing. Warranties that aren't at the top of the curve as far as length or coverage are where they are for a reason- the analysis has been done, and the engineers or the big wig felt that a longer warranty would be a financial drain on the company.

I would agree 100% that an engine's use in a genset has very little to do with the soundness of the engineering that went into it.

RE: Engine Reliability Data

I know for a fact that the use of a particular engine in a gen set has little to do with reliability and much more to do with availability and cost. Trying to source generator engines is a major problem and several of the larger companies will pretty much take what they can get and then adapt it as required to work in the application and I have seen that a lot of that type of adaptive engineering is not very well done compared to the level of work put into the engine by the OEM.

RE: Engine Reliability Data

Quote (Tmoose)

So Chrysler engines statistically last lifetime/60,000 X as long as Toyotaa engines ?

http://toyota.custhelp.com/app/answers/detail/a_id...

https://www.chrysler.com/en/lifetime_powertrain_wa...

Certainly not.

But read the fine print on the 'lifetime' warranty- it applies only to the first registered owner.

What percentage of owners of Chrysler product keep their vehicles past 60,000 miles? 70,000? 100,000?

I can guarantee you that Chrylser knows those numbers, and that their estimates of what a lifetime warranty would cost them were a huge part of the decision to offer one.

RE: Engine Reliability Data

It's that duty cycle part that's the problem. Variations in vehicle weight and local terrain will greatly affect the loads that are put on various parts.

So far as I've ever noticed, it is the surrounding support equipment that are limited life. From shenanigans like Ford using sleeved plugs with inappropriate seals to prevent carbon-seizing to poor quality harness designs on GM trucks. Sure, there are some standouts like when Dodge set the exhaust manifold too close to the head causing thermal expansion related head gasket leaks or the Toyota sludge issue, but these may not show up in steady-state or accelerated testing (somewhat sure if they had, Chrysler/Dodge and Toyota would have noticed and fixed the problem instead of deciding to burn the crap out of some customers.)

Were it possible, it would be best to see what engines are coming through rebuild companies.

RE: Engine Reliability Data

(OP)

Quote (3DDave (Aerospace))

but these may not show up in steady-state or accelerated testing (somewhat sure if they had, Chrysler/Dodge and Toyota would have noticed and fixed the problem instead of deciding to burn the crap out of some customers.)

I bet they showed up, but could they fix the issue on budget on time? Usually I see the issues like that one being ignored willfully, then downplayed by people trying to protect their own ass, then their boss downplays his inaccurately low estimate of how big of an issue it is, then they launch the product without fixing it. All the while, there was a test technician and engineer who knew about it all along.

To anybody in here working in upper management of a manufacturer, do skip-level meetings with your lab techs and test engineers before a product launches. They actually observe every issue and have nothing to lose by giving you an honest answer. Or just ignore them long enough to make them stop caring. Might help quarterly profits until the warranty returns come back and your customers abandon you.

I've seen this scenario a few times in person. A product consistently starts showing catastrophic infant failures despite there not being any design changes from what was normally a reliable product, then people assume its a fluke and conveniently ignore the fact that its a consistent failure. Then the issue gets so badly that somebody finally decides to investigate whether or not the product is being heat treated properly... Then it turns out that its not being heat treated properly. Now there are a few hundred units of this very expensive product that will quickly become conversation pieces for their outrageously young and dramatic failure.

"Formal education is a weapon, whose effect depends on who holds it in his hands and at whom it is aimed." ~ Joseph Stalin

RE: Engine Reliability Data

Quote (Panther140)

Usually I see the issues like that one being ignored willfully, then downplayed by people trying to protect their own ass, then their boss downplays his inaccurately low estimate of how big of an issue it is, then they launch the product without fixing it. All the while, there was a test technician and engineer who knew about it all along.

This is the point of view of someone with real powertrain design experience ha ha

RE: Engine Reliability Data

Quote:

Certainly not. But read the fine print on the 'lifetime' warranty- it applies only to the first registered owner. What percentage of owners of Chrysler product keep their vehicles past 60,000 miles? 70,000? 100,000?

Like the current Mopar V6s and V8s with systemic wear of rocker arms and valve seat inserts dropping. They are cheap to build, make lots of power for the unit cost, but the rebuild shops are drowning in them today. They did usually last long enough to get out of warranty/first owner, or the rebuild shops wouldn't be getting the business. And there's absolutely no maintenance the owner can do which will prevent these failures. They're designed in.

Quote:

That method doesn't work as well when vehicles like the 3.5L ecoboost come into question. I like the idea of a v6 turbocharged half-ton, but I also know that this platform is vulnerable to higher deviations from expected endurance.

I admit to being skeptical a turbo 3.5 could survive the rigors of commercial pickup use, but so far, it seems to be more reliable than the old lump OHV8s it replaced. Would be of interest to read of the engine failures and what causes them.

Having said that, I regularly see owners managing to kill some part of the Dodge Ram 3500 with the Cummins. As the pickup platform evolves greater competency, gypsy truckers are putting them into over-the-mountain light-duty 5th-wheel service. That's outside the performance envelope, especially when some numbnuts also stops by "BullyDog" for a "tuner" upgrade. I saw one owner burn up the OEM clutch while proudly showing how his "tuner" would pull the grade without a downshift. The tuner produced enough torque to slip the disc while it was engaged.

jack vines













RE: Engine Reliability Data

Is it important to distinguish between 'durability' and 'reliability', or are they always closely related?

RE: Engine Reliability Data

(OP)

Quote (drwebb (Automotive))

Is it important to distinguish between 'durability' and 'reliability', or are they always closely related?

I'd consider it important to distinguish between durability and reliability in a few cases.

Reliability, to me, is measurable by the likelihood that an engine will operate over a given period of time without failing in any way that takes it out of service for any measurable length of time.

I judge durability by the length of serviceable life of an engine working at a given duty cycle in reasonably controlled conditions. It can be thought of as how closely the amplitude of the loading of the engine's major components (crankshaft, con rod, piston, block, heads) are to the fatigue limit of the parts.

If we're discerning, I want an engine that is reliable at given duty cycle for the longest amount of time. The high duty cycle makes endurance necessary, by nature.



"Formal education is a weapon, whose effect depends on who holds it in his hands and at whom it is aimed." ~ Joseph Stalin

RE: Engine Reliability Data

I've owned the same Volvo 142 since 1978. I don't know how many miles are on it but its a lot. I'm speaking from first-had experience in keeping cars on the road for a long time. I've always done it.

Keeping a car on the road for a long time is a winner from both a financial and environmental standpoint. The drawbacks are that engines aren't what you get tired of; its worn out driver's seats (particularly if you weigh over 200 lbs) and worn out suspensions. A good seat overhaul can cost a grand; nobody spends it. As a good working rule, suspensions wear out long before engines do nowadays but almost nobody bothers to overhaul suspensions. Even if you keep up the suspension, there will be creaks and groans and pops that develop and aggravate you. Automatic transmissions can easily cost as much as engines, and they don't last as long. Manual transmissions are generally bulletproof if you don't abuse them. Clutches' lifespans depend too much on driver ability and type of driving to generalize about. Diesels rarely make economic sense for most people as diesel maintenance and diesel parts cost too much more than gas. Most of the paint durability problems I think have been fixed, but that could change tomorrow courtesy of the EPA.

Here's the secret to keeping a car on the road for a long time: When something breaks, fix it. That Volvo wasn't a particularly good car then, much less now. But I fixed what broke. Failure to fix the small broken things always leads to either big broken things or stupid aggravation about the broken item that makes you dump the car and get another one. I recall reading a figure in the '70's that the production of a new car generated 20,000 lbs of pollution. I don't doubt it then and I am sure it is no better now--whatever breakthroughs in pollution control we've had have been overmatched by increased car weight and complexity. So every year you don't buy a new car, you are saving the production of ten tons of pollution. That's an excellent reason to keep older cars running.

And I'm selling the Volvo soon anyway. Cars are one hell of a lot better drive, every single last one of them, than that one is. Parts availability has gone to hell for the older Volvos, and I wouldn't bet on anyone's parts availability, except pickup trucks, over more than 20 years nowadays. Probably a lot less than that, and even then there is the problem of putting in 10 or 20 year old new parts that just don't last like 2 year old new parts. Particularly true for rubber and electronic parts.

Boss Kettering said that the automobile was the greatest single invention for economic waste that had ever been made. He was right and that is how you have to look at cars--economic waste. Just try and minimize it, OK? There's a lot better ways of spending money and the damned things are so hard on the environment.

RE: Engine Reliability Data

Agree with you 100% apart from the driving experience part. The car as a negative investment..... I like to get maximum value from mine.

The 5 working cars in our household have about 780,000 miles and 116 years between them. This is slightly skewed by having one very old one ('67 Triumph) and one very high miles one ('96 Audi A6 @ 300k).

The nastiest drive would be the '00 Seat Arosa, 64 asthmatic, clattery NA diesel ponies, the most boring the '06 Kia Ceed. The '96 Audi A8 is dropping to bits, but still a fine drive and properly quick even by today's standards, the A6 just keeps on trucking - the I5 TDI is very reliable, but the UK climate is taking it's toll on the underbody now. However, for a cross country run in the sun or blast around the Alps the '67 Triumph cannot be beat......

Nick

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