Why Do Vehicles "Wear Out"

[Burt]

I keep cars until they are ready to be scrapped. Here why I got rid of them.

1965 mustang w/102,000 miles- severe rust, front suspension, engine burning oil

1981 capri w/102,000 miles. Head gasket leaking, manual transmission hard to shift. Wish I would have put a used tbird turbo 4 in it.

1987 Taurus wagon with 110,000 miles. Had fixed ac twice and it was shot again.severe cosmetic rust and head gasket leaking.

1991 Eagle Talon w/123,000 miles - had overhauled manual transmission once and it needed another.

1998 Windstar w/209,000 miles - needed $1000 repair for tuned intake manifold gizmo and suspected bad front wheel bearing wasn’t cheap to replace or could’ve been transmission. Seemed to be nickel and diming.

I expect all these cars went to the junkyard.

 

[notharry]

I have seen an engine with over 100000 miles with perfect everything with a hole in one piston because someones solution to a stuck egr valve was to turn the idle up so it would idle better. I have seen engines with over 300000 miles that run perfectly with zero wear on the mains and rod bearings. Rings and bore were worn out of spec. Honda civic Cvcc in 1979 that ate camshafts every 60,000 miles. Mains and rod berings worn engine replaced at 120,000. w used. never a future issue after anothe 80,000.

My point Some things as just defective, some improperly maintained and some wear out. Some are a bad design across the board. I think its very important for us all to share experiences. Then we all stay away from these problem vehicles.

 

[John105]

Even the blades on ice skates wear out, and there is very little friction. They are able to turn a solid into liquid. Now imagine a motor vehicle.

 

[Pablo]

We have forum members who get tired of driving the same car after 18 months.

Came here to say this is a feature of many in our population.

Most car get handed down/sold for lower and lower $ until the last owner hardly gives a darn. Car agonizingly dies.

 

[supton]

The car get in an acident. Well if the vehicle is a twisted mess, its probably not financially viable. Have insurance

Had insurance on one car that was totaled. $3,500 I think was the payout—not replacing with only that much. Having cash on the side to replace when the value drops low is better imo. Having cash in general is good, as is a spare car, so that you can drop off at a garage and still get around—or repair in your spare time.

 

[eljefino]

Surely you jest? I know there is likely a control module of some sort in there, maybe an airbag—but why would it need to be vin coded?

They do it to be jerks and for planned obsolescence. They say it's for theft protection or some other lame excuse.

I have a HVAC brain in my wife's Prius that's out of a higher level Prius. It works fine but has a code for not seeing the rain sensing wiper module. Doesn't light any lights so I don't consider it a problem.

 

[Owen Lucas]

When the cost of repair is no longer worthwhile. This could be a 5 year old electric kia that needs a $17k battery pack. I'm sure 99% of the car is fine except for the battery pack, but it's basically worn out, financially.

 

[svtrit]

Surely you jest? I know there is likely a control module of some sort in there, maybe an airbag—but why would it need to be vin coded?

Yup. I had a fleet of F150’s we would pull the seat out of for equipment. We mixed up two, which ended up in different states. Both had the airbag light illuminated and the one I took to Ford required the seat from the other for repair.

 

[supton]

Yup. I had a fleet of F150’s we would pull the seat out of for equipment. We mixed up two, which ended up in different states. Both had the airbag light illuminated and the one I took to Ford required the seat from the other for repair.

Seems wrong--won't be long before TPMS sensors are VIN coded too. Sheesh.

 

[y_p_w]

Remember, every single component on a vehicle has a design life. Every component on a vehicle will wear.

Generally when a customer decides to stop repairing a vehicle it is for one of a few reasons. The biggest one here in the northeast is rust that is compromising the structural integrity of the vehicle to the point that it no longer passes inspection in this state and repair isnt practical. The second, which sometimes goes with the first, is lack of available repair parts. The third is that the vehicle needs repairs and it no longer suits the customers needs.

When faced with a major repair, the question most owners ask is "What would you do if it was your vehicle" which is my least favorite question to answer, because what I would do has little impact on what is the best choice for you.

But the reality is that there will always be a bathtub curve for failure over time and/or ultimate longevity. Very little out there just fails on a dime other than catastrophic failure such as fatigue resulting in sudden failure (like an axle breaking).

You can take a look at older vehicles or aircraft that are still functional. But that's a matter of spending an inordinate amount of money on new parts, carefully inspecting parts, and possibly cannibalizing fleets of retired aircraft for irreplaceable parts that are still in good enough condition to put back in service. As a matter of practicality, keeping a 1930 Ford Model A running is not a matter of common sense. It's not being done for practical transportation.

 

[97prizm]

Now?

1.- Crashes. Less people know how to drive. Just saw a 8 car accident yesterday. Not something you get a choice in…..

2- Weather- Hurricanes, tornadoes, floods, etc. Many more of these now- takes more cars out now.

3- Lack of care. Put as little money is as possible, and watch it slowly burn……

4- If it survives the above, many cars simply die a slow rusty death………

You’re welcome.

Part of it is all of the electronics. Cars are able to be plugged in and upgraded but electronics don't like voltage spikes, water or dirt.

 

[Arc]

Wearing out is expected and something that happens to everything. Planned obsolescence is a dirty little trick we've seen for a while now even if they won't admit it.

 

[y_p_w]

Part of it is all of the electronics. Cars are able to be plugged in and upgraded but electronics don't like voltage spikes, water or dirt.

Electronics can be pretty robust. But I'd think the weak point for the longevity of most consumer electronics is the use of electrolytic capacitors.

 

[daves87rs]

Part of it is all of the electronics. Cars are able to be plugged in and upgraded but electronics don't like voltage spikes, water or dirt.

Very true!

 

[notharry]

tpms are coded of sort as they are read by the vehicle via a radio signal. Because they are batery devices, this needs to happen. Seats are containing air bags now and thus a part that needs to be reliably monitored and. We as mechanics and car lovers are going to have to get more and more into complicated equipment. According South Main Auto on youtube, (check them out) short term subscriptions can be purchased thru a third party for programing, repair and diagnostic information. Even a manufacturer has a web service for this task with factory support. (Yes the manufacturers profet from this) Youtube is also a priceless resourse for good information to help us repair our own vehicles. Pine hollow diagnistics is great as well. These fellas know their stuff. Some obviously do not. Electronic failures and most commonly from a bad solder joint, capacitors, as well as other internal failures. Check and clean your grounds periodically under the hood and vehicle. Oil or grease or otherwise add corrosion protection to the terminal ends. or any exposed bare wires especially the braided grounds. Check your other grounds if you see them inside the car. A bad main ground can cause electrolysis in the engine in the head gasket area, (according to some especially subaru experts). Back grounding through another (smaller) device, sometimes even throught bearings causing the bearing internals to spark arc and pit. In my opinion, bad grounds are one of the most comon failures and the most overlooked, especally in the salt belt and adds to component failures.

 

[supton]

Electronics can be pretty robust. But I'd think the weak point for the longevity of most consumer electronics is the use of electrolytic capacitors.

Certainly is, although one fellow I've chatted with has said that for their high reliability products, electrolytics are not allowed. Wild guess says he doesn't work in automotive, I'll bet. At least most electrolytics are reasonably easy to replace--assuming you can open the widget in the first place, and get it reasonably sealed back up.

Seats are containing air bags now and thus a part that needs to be reliably monitored

True but there's no reason for it to be VIN coded, IMO. Talking to it, asking it to do various checks, should not require anything beyond an address on a buss. Nothing other than the car's ECU should be connected to the buss.

Or maybe I'm wrong? maybe the intensity of the airbag inflation is altered per vehicle (very likely) and this seat is used in multiple vehicles (how likely?). I just have a hard time seeing why each module has to be coded--it's not like it needs to have its IP address (CAN address) hand picked per car. And for some reason I tend to think a seat is manufactured per vehicle, not a seat is designed to be in multiple platforms and thus the airbag inflator is somehow controlled by more than a couple of bits (low, medium, high inflation force).

Even if there is a need to configure the seat per chassis... ECU checks the seat, finds a mismatch in startup, says "hey you're in a 2014 Honda CRV now" and the seat adjust accordingly. Or the ECU says "parameter xyz needs to be 123" at each power up and it's done.

So says the guy who misses his 1999 Camry and usually drives with all electronics off...

 

[Number_35]

Why Do Vehicles "Wear Out"​

Entropy

View attachment 260838

A chemistry textbook from my high school days used the analogy of a bunch of table tennis balls grouped in a tight array sitting on a shelf in the back of a station wagon. They had potential energy as they sat a foot or so above the cargo floor of the wagon.

As the car was driven, the balls moved around and eventually wound up scattered all over the floor.

 

[Creekside]

It’s been my experience that “usually” it’s a transmission related failure. The average driver will take their car to a quick lube where at least the engine oil is changed and basic fluid checks are done. I’d be willing to bet that most of the vehicles on the road are overdue for trans maintenance especially with the lifetime fill push from the manufacturers. Many people won’t spend the $2-4k to R&R a transmission on a vehicle with 150k+ miles. Many people don’t even have that kind of funds put back.

 

[y_p_w]

Certainly is, although one fellow I've chatted with has said that for their high reliability products, electrolytics are not allowed. Wild guess says he doesn't work in automotive, I'll bet. At least most electrolytics are reasonably easy to replace--assuming you can open the widget in the first place, and get it reasonably sealed back up.

I'm thinking they probably don't contain electrolytic in most car applications. My understanding with ECU failure is that typically the whole unit gets replaced. I really hate analog electronics, but I do remember doing a board-level project once. We generally wanted a big capacitor to help smooth out the power delivery, and I bought a bunch of polyester capacitors. My understanding is that unless they randomly short or overheat, they'll last forever.

 

[supton]

I'm thinking they probably don't contain electrolytic in most car applications. My understanding with ECU failure is that typically the whole unit gets replaced. I really hate analog electronics, but I do remember doing a board-level project once. We generally wanted a big capacitor to help smooth out the power delivery, and I bought a bunch of polyester capacitors. My understanding is that unless they randomly short or overheat, they'll last forever.

I'm not sure what the wear mechanism for polyester (mylar) would be; they aren't popular due to low k value / large size, but are still prevalent in low cost audio gear (aka "greenies"). I wouldn't think to use them on power supplies, I have no idea what their frequency response is but I would have guessed mildly inductive. Then again, there's a bunch of different poly-type capacitors and putting them all into one bin would miss the point--I might be thinking of the wrong polyester.

I recall when 100nF was a "big" monolithic ceramic but now I think you can get 47uF in reasonable voltage rating. It's changed quite a bit over the years and there seems to be no good reason to design with fragile tantalums anymore. Between high k value ceramics and smaller size, one has a lot of options now for design.

Of course SMT chip caps are notorious for failure modes due to board warping, but that's a different problem... I'm amazed that more circuit boards don't fail due to barrel cracking from heat cycling, or other woes from age. IC's have gotten to be pretty good at being long life but even they too can random decide to die (but I suspect secondary effects are more to blame, like not sealed up quite as good as one thinks).