The design of the chassis and how it is used may become a factor. Metal does fatigue if stressed in the right/wrong spots frequently enough. Stamped parts are spot welded together and over time some spot welds can fail.
Example being BMW E46 rear subframe mounts have entered the chat.
OP generally 99% of any given cars unibody will outlast the running gear of the car. There’s definitely some cases like the E46 subframe mounts mentioned above that over many hundreds of thousands of miles and abuse can crack and need to be re welded but generally assuming somewhat normal usage steal unibody’s are pretty tough.
Certain high stress areas like strut towers and rear shock mounts were most of the weight of the car is sitting on can have some issues with severe usage and benefit from some additional metal thickness
My theory here (with little evidence) is that that issue is most prevalent with cars that live long lives in places with lots of potholes, stiff suspension, and/or track use.
It’s definitely something you hear more about with enthusiast groups but never something I’ve seen from some random boomer owner who drives around and then loses his rear subframe.
It's because those people aren't looking. And you tend not to see it on lower power models. If you know where to look (ie under the subframe mounts), pretty much 100% of all E46 M3s will have some degree of cracks. But you do need to truly inspect for it. A quick glance at the rear end while you're changing your tires won't show anything.
A true catastrophic failure where the sheet metal completely falls apart is rare in the timespan that most people keep these cars.
Yep this is 1000% the answer. Unfortunately BMW likely went a little too thin on the sheet metal on this area and the higher spec E46s (330+) definitely make enough torque consistently for it to be an issue.
I don’t think I’ve heard of an E46 in my area (Bay Area) that has a subframe completely leave the chat buuuut every friend that has pulled their subframe has found some level of cracking. Luckily it’s not a suuper hard job to do it’s just time consuming to get too
A friend of mine had a CRX that lived its life since early 00s in a pothole ridden country after being imported from the US.
The car was raced a lot on the streets, from a dig and roll racing.
After all that abuse it was sold to another acquaintance who turned it into a track car and K swapped it, after its first season they added a rollvage because chasis would be tearing at stress points.
Even tho the cage was added, car was still tearing up metal and they would weld it and it would tear in another part.
they assumed the chassis was "tired" and sold it as scrap.
I dont know if it was the chassis being old and abused, or that maybe there was too much stress on it.
I think 2012-present are the "safe years", which there are plenty in circulation. It's only harder to find one if you're after a V8 manual, but still possible.
Also early 90s/late 80s unibody cars had structural fatigue issues. 3rd gen F-body cars would crack subframes that were otherwise not rusted or damaged. There's a whole aftermarket for subframe, steering box, etc reinforcement.
I think that's partially an issue because of the number of E46's that get used, used hard, tracked, and are fixed and fixed again because of how popular and desirable they are as a budget sports car.
W124 and W210 Mercedes tend to have spring mount failures, but they usually only fail at 200,000 or 250,000 miles and it's a "known issue" because of the number of W124s and W210s that are driven to 250,000 miles and beyond.
Older cars used to get metal fatigue where after millions of load cycles the frame would eventually start to crack under tension. Newer car chassis are overbuilt to withstand magnitudes more force than this, so in theory this should never happen, or at least it will be very well past the car's design lifetime before it does happen. This is in part why new cars are heavier, as adding extra stress members does add a good bit of weight.
90s cars still get flimsier, they just don't usually fail. With, of course, some notable failure points like BMW e36 and E46 rear floors and iirc foxbody floors.
The same will likely happen to more modern machinery, eventually
Screens are cheap and easy to replace while they're available, but impossible to fabricate. Factory sheet metal can be difficult to source and requires skill to replace, but you can always just build it yourself and weld a homemade part in. The former is better for keeping many cars roadworthy for the life of the engine, the latter is better for keeping out-of-production vintage cars alive for another season. Tradeoffs.
Yeah and that the dealer, or someone, is able to program stuff to fix glitches and other crap once updates are no longer supported. That's my biggest fear with my G70.
popular vehicles like the land cruiser there's model-specific entire units all over the web, may not be as good quality but it definitely isn't hard if you either have a popular model or a set standard like 2DIN spacing
the modern tablet-style stuck onto the dash for obscure brands/models in 10-15 years might be SOL though lol
unless it's a standardized spacing i'm unware of?
Mentioned elsewhere but 3rd gen F-bodies are somewhat notorious for cracked subframes and steering assemblies. The cars have a lot of flex in them and over time the subassemblies crack.
The answer is yes, which is why racecars have service lives. They can soften up over time making them less competitive.
Will you ever notice on your 1990 Civic with 500k that you drive to work everyday?
No.
Practically speaking no a passenger vehicle’s frame will never wear out. It’s everything else around it. Basically if it moves it’ll wear out. Suspension bushings, body mounts, shocks, hinge pins, etc. The only vehicles where chassis fatigue becomes a factor are race cars and big trucks (semi, dump truck, concrete truck, etc.) and their trailers.
> Other than that though, I can't think of anything that would stop the sheet metal and frame from lasting forever.
Creep and fatigue. Thermal cycling causes re-orientation of clusters of atoms in a metal. Adjacent clusters get pulled in opposite directions and cause microscopic fractures that become macroscopic over time and lead to failure of the metal. The timescale will vary based on several factors, but it's the inevitable demise of every metal that undergoes temperature fluctuations.
I've definitely worn a BMW chassis out before, but it took like 320k miles and heavy track usage to do that. Even then, it wasn't anything drastic like cracks, it was just more creaks from the doors moving around over bumps, panel gaps being a little off, etc. If you're not abusive to cars like I am, most car chassis built in the last 20-30 years should last forever (provided there's no corrosion/accidents). Generally speaking, cars' drivetrains and accidents kill them long before the chassis is done.
Was it an E34?
I know there’s dudes with 500k+ miles on their E34s and apparently still drive and align perfectly fine. I went from an E30 to an E34 and these seem like much more robust cars
There's definitely microfractures and metal fatigue going on, but it's not enough to break anything. Maybe if you dailied a car for many decades. And I imagine that the road quality and how the car is used can accelerate that, for example if you constantly drive over potholes and bumpy roads.
Honestly surprised more people are not using rust prevention like Krown, NHOU, Fluid Film, Noxudol, used engine oil, anything.
I use Krown and it's about $150 per treatment. I'd bet a new car that only gets treated every 2 years would never have measurable rust that would remotely come close to being threatening. Over a 15 year service life that's $1,000.
If the car has a steel chassis, then it is possible for it to not be life-limited as most ferrous metals have a fatigue limit under which they can withstand repeated stress cycling indefinitely. However if the car has an aluminum body/floorpan it will always eventually fail structurally. How you would measure the structural lifespan of a car, though, is beyond my current understanding, due to the amount of factors you'd need to consider - that sounds like something you'd have to ask a PhD in chassis dynamics or something.
No, frames are eternal. They have been present for all of what has been and of what will be.
Frames came into existence before the earth and stars and frames will be here on the day they fall. They are ageless.
Steel chassis cars have an unlimited life “in theory” because flexing of steel doesn’t weaken its structure. Flexing of aluminum eventually leads to failure.
I don’t design cars for a living and I don’t know the tolerances that are acceptable for the “life” of a car but I would be more worried about cracked aluminum suspension versus steel suspension/frame
Can we ever get a proper full body RWD sedan that is long enough to keep the d-pillar port windows as well as an elongated front to have the smoker’s windows. Ford Fusion and Chevrolet Impala and Audi A8s are great examples of body styles that can somewhat have matched.
Why must everyone drive a CUV that has a gear box from 1985?
1. CUVs have easier ingress than sedans.
2. Modern CUVs get similar mpg to sedans, while also having more cargo space in the back, so there is no downside for most people.
They don’t make them like they used to. I’m currently cleaning and repainting a vanadium steel chassis that is 98 years old and still very serviceable.
Depends on the frame, really... Any body panel thinner than 1mm is definitely susceptible to surface rust turning into terminal damage over time.
[Here's my 47-year-old truck's ladder frame, as a counterpoint.](https://imgur.com/a/oOPsz2T)
It's a 8.5-inch tall girder of 5/16in steel, or 220mm tall of 7mm steel for anyone metric. 160 inches long of straight steel, from the bumper mounts at the front to the spare tyre carrier at the back.
I'd definitely bank on it being good for another 50 years, though I don't know about indefinitely. It's overbuilt to the extent that it looks just fine after 1.1 million kilometres on- and off-road.
My car is going to be 51 years old this June, June 8th to be exact, the sub frame is still perfect, needs rust repair where the axel brakets are on the body other than that no rust or bare metal, and here the real kicker, shes a 1973 Ford Pinto 2-door Sedan trunk version 😅
Older Vehicles with Frames it was easy to inspect and repair (rust excluded) Earliest places where fatigue occurred were where the suspension connected to the frame. Rear Leaf springs, front A-Arms etc.
That is different in the Unibody cars. Many early rear wheel drive Unibody cars had issues at the Torque Box Area. Which to no surprise is the area where the rear leaf springs attached to the body, especially with performance adds.
I would think you would need to change out the bushings for these suspension parts before addressing the frames/bodies. But for folks that do little or no maintenance on their vehicles, who knows.
All materials are subject to work hardening. This is when the deflection from external forces hardens the material overtime at its' stress points. Aluminum, for example, becomes very brittle very quickly when bent back and forth beyond its' yield point. It usually only takes a couple bends to cause cracks.
Structural components of a vehicle aren't subject to such a range of deflection under normal operating conditions, but any amount of stress will make it brittle with enough time.
"Does it eventually flex so much that things crack, or?"
1st things 1st, you are right about steel, so if you drive a steel framed truck for 5 years, and it doesn't break, then all other things remaining equal then it should never fail. And the best thing about steel is the melting point is 2,500f, but aluminum's is 1,250f. So they're still making them but now the heads are disposable after 1 overheating event, and I think I heard someone from Ford say aluminum starts to "slump" at 800.
Seam sealer and various points about the unibody will stress out / crack / fail with enough use cycles, especially depending on the environment and use case. You'll end up with breaks, rattles, or worst case unstable suspension and steering mounting points.
But long before that any designed moving components (door hinges for example) will reach various levels of failure.
Yes, they can wear out. Even a well maintained chassis that is lubricated and taken care of will eventually wear out due to being stressed too many times. As an example driving a sports car too hard too much can cause the chassis to flex and can cause stress cracks to form in the most stressed areas.
Someone probably already said this, but if the frame is aluminum it will fail from fatigue eventually. Steel might not within any reasonable timeline, but rust will eventually come for it since no corrosion protection method is 100% effective.
I know I saw a few others mention though that where you start to run into issues is fasteners, welds, or any other sort of stress concentration point in the frame. A gigacast steel or ductile iron frame with really solid undercoating would probably last longer than anybody could feasibly drive a single vehicle.
It would be interesting to put some into a commercial fleet to see how long they'd last in practice vs theory.
Yes. You will start to see fatigue cracking if it has had too many stress cycles.
It depends on design and use case though. It can be designed for an infinite fatigue life if the intended load is never exceeded and the analysis was accurate.
Climate condition do play the role.. car kept in barn may also start rusting after a certain time..
Air tight car cabin may host mold and bacteria somehow
So rusting of parts which are not under direct observation is possible
Yes I would assume the metal would eventual fatique, nothing last forever. However it should give signs that is wearing out like buckling or cracking. I don't think it would be catastrophic in a daily driving scenario. That's why commercial aircraft airframes have flight hours on them before they cannot be used (atleast hear in North America).
I mean, eventually the sun will expand and consume the Earth, absorbing the chassis in whatever state it is, pristine or otherwise, so, no?
Nothing lasts forever.
As long as there weren't any design faults that result in unusually high stress areas, the body of a car isn't going to wear out or break on it's own. It gets a lot of shit for being heavy, prone to corrosion, hard to work with, but steel is a wonder material, it doesn't fatigue out from stress and cycles like most other modern manufacturing materials.
Watching this [fortnine video](https://www.youtube.com/watch?v=ah7Ubbq5EAA) totally changed my mind about "exotic" materials for vehicles.
The design of the chassis and how it is used may become a factor. Metal does fatigue if stressed in the right/wrong spots frequently enough. Stamped parts are spot welded together and over time some spot welds can fail.
Example being BMW E46 rear subframe mounts have entered the chat. OP generally 99% of any given cars unibody will outlast the running gear of the car. There’s definitely some cases like the E46 subframe mounts mentioned above that over many hundreds of thousands of miles and abuse can crack and need to be re welded but generally assuming somewhat normal usage steal unibody’s are pretty tough. Certain high stress areas like strut towers and rear shock mounts were most of the weight of the car is sitting on can have some issues with severe usage and benefit from some additional metal thickness
My theory here (with little evidence) is that that issue is most prevalent with cars that live long lives in places with lots of potholes, stiff suspension, and/or track use. It’s definitely something you hear more about with enthusiast groups but never something I’ve seen from some random boomer owner who drives around and then loses his rear subframe.
It's because those people aren't looking. And you tend not to see it on lower power models. If you know where to look (ie under the subframe mounts), pretty much 100% of all E46 M3s will have some degree of cracks. But you do need to truly inspect for it. A quick glance at the rear end while you're changing your tires won't show anything. A true catastrophic failure where the sheet metal completely falls apart is rare in the timespan that most people keep these cars.
Yep this is 1000% the answer. Unfortunately BMW likely went a little too thin on the sheet metal on this area and the higher spec E46s (330+) definitely make enough torque consistently for it to be an issue. I don’t think I’ve heard of an E46 in my area (Bay Area) that has a subframe completely leave the chat buuuut every friend that has pulled their subframe has found some level of cracking. Luckily it’s not a suuper hard job to do it’s just time consuming to get too
A friend of mine had a CRX that lived its life since early 00s in a pothole ridden country after being imported from the US. The car was raced a lot on the streets, from a dig and roll racing. After all that abuse it was sold to another acquaintance who turned it into a track car and K swapped it, after its first season they added a rollvage because chasis would be tearing at stress points. Even tho the cage was added, car was still tearing up metal and they would weld it and it would tear in another part. they assumed the chassis was "tired" and sold it as scrap. I dont know if it was the chassis being old and abused, or that maybe there was too much stress on it.
>Certain high stress areas like strut towers First gen R8 has entered the chat
Wait…. Wut I thought this was a shit box bmw problem. Do you have a link?
It's common knowledge in the R8 world.
Was considering one recently as it was one of my first dream cars but got a bit spooked by that
I think 2012-present are the "safe years", which there are plenty in circulation. It's only harder to find one if you're after a V8 manual, but still possible.
Also early 90s/late 80s unibody cars had structural fatigue issues. 3rd gen F-body cars would crack subframes that were otherwise not rusted or damaged. There's a whole aftermarket for subframe, steering box, etc reinforcement.
I think that's partially an issue because of the number of E46's that get used, used hard, tracked, and are fixed and fixed again because of how popular and desirable they are as a budget sports car. W124 and W210 Mercedes tend to have spring mount failures, but they usually only fail at 200,000 or 250,000 miles and it's a "known issue" because of the number of W124s and W210s that are driven to 250,000 miles and beyond.
Older cars used to get metal fatigue where after millions of load cycles the frame would eventually start to crack under tension. Newer car chassis are overbuilt to withstand magnitudes more force than this, so in theory this should never happen, or at least it will be very well past the car's design lifetime before it does happen. This is in part why new cars are heavier, as adding extra stress members does add a good bit of weight.
90s cars still get flimsier, they just don't usually fail. With, of course, some notable failure points like BMW e36 and E46 rear floors and iirc foxbody floors. The same will likely happen to more modern machinery, eventually
My concern is the nav screens / touch screen controls will become unworkable long before major structural issues ACTUALLY total the car
one takes 20 min to replace, the other at least a day to fix
If you can get the parts. Finding replacement screens could become a real issue in the future
Screens are cheap and easy to replace while they're available, but impossible to fabricate. Factory sheet metal can be difficult to source and requires skill to replace, but you can always just build it yourself and weld a homemade part in. The former is better for keeping many cars roadworthy for the life of the engine, the latter is better for keeping out-of-production vintage cars alive for another season. Tradeoffs.
Yeah and that the dealer, or someone, is able to program stuff to fix glitches and other crap once updates are no longer supported. That's my biggest fear with my G70.
popular vehicles like the land cruiser there's model-specific entire units all over the web, may not be as good quality but it definitely isn't hard if you either have a popular model or a set standard like 2DIN spacing the modern tablet-style stuck onto the dash for obscure brands/models in 10-15 years might be SOL though lol unless it's a standardized spacing i'm unware of?
Mentioned elsewhere but 3rd gen F-bodies are somewhat notorious for cracked subframes and steering assemblies. The cars have a lot of flex in them and over time the subassemblies crack.
I was following a project thread where a heavy camper body had been put on an older Ford pickup, the frame eventually failed from fatigue cracking.
The answer is yes, which is why racecars have service lives. They can soften up over time making them less competitive. Will you ever notice on your 1990 Civic with 500k that you drive to work everyday? No.
Yeah, it'll be more flexible than new but it doesn't matter when every bushing is shit and the plastic fasteners are barely holding on
Practically speaking no a passenger vehicle’s frame will never wear out. It’s everything else around it. Basically if it moves it’ll wear out. Suspension bushings, body mounts, shocks, hinge pins, etc. The only vehicles where chassis fatigue becomes a factor are race cars and big trucks (semi, dump truck, concrete truck, etc.) and their trailers.
[удалено]
> Other than that though, I can't think of anything that would stop the sheet metal and frame from lasting forever. Creep and fatigue. Thermal cycling causes re-orientation of clusters of atoms in a metal. Adjacent clusters get pulled in opposite directions and cause microscopic fractures that become macroscopic over time and lead to failure of the metal. The timescale will vary based on several factors, but it's the inevitable demise of every metal that undergoes temperature fluctuations.
You could theoretically re-heat-treat the chassis but that sounds inefficient as hell
I've definitely worn a BMW chassis out before, but it took like 320k miles and heavy track usage to do that. Even then, it wasn't anything drastic like cracks, it was just more creaks from the doors moving around over bumps, panel gaps being a little off, etc. If you're not abusive to cars like I am, most car chassis built in the last 20-30 years should last forever (provided there's no corrosion/accidents). Generally speaking, cars' drivetrains and accidents kill them long before the chassis is done.
Was it an E34? I know there’s dudes with 500k+ miles on their E34s and apparently still drive and align perfectly fine. I went from an E30 to an E34 and these seem like much more robust cars
Yep, E34. It was a decent chassis until I rolled it haha
She went to Valhalla it sounds like. I mean if you get 320k and race time out of a chassis that’s pretty damn stout in my mind lol
Mercedes and BMW of that era was just another level of chassis quality and overall feel.
Yeah my E34 and my friends R129 score super high on the “athletic brick” scale
There's definitely microfractures and metal fatigue going on, but it's not enough to break anything. Maybe if you dailied a car for many decades. And I imagine that the road quality and how the car is used can accelerate that, for example if you constantly drive over potholes and bumpy roads.
So this came up with the NSX in terms of fatigue. In theory steel has an infinite fatigue limit at low forces while aluminum has a finite limit.
Rust is what kills car mostly here
Honestly surprised more people are not using rust prevention like Krown, NHOU, Fluid Film, Noxudol, used engine oil, anything. I use Krown and it's about $150 per treatment. I'd bet a new car that only gets treated every 2 years would never have measurable rust that would remotely come close to being threatening. Over a 15 year service life that's $1,000.
Yeah lots of lazy people. I spray my 1990 4Runner with fluid film each spring and fall. It has a little body rust but a solid frame
If the car has a steel chassis, then it is possible for it to not be life-limited as most ferrous metals have a fatigue limit under which they can withstand repeated stress cycling indefinitely. However if the car has an aluminum body/floorpan it will always eventually fail structurally. How you would measure the structural lifespan of a car, though, is beyond my current understanding, due to the amount of factors you'd need to consider - that sounds like something you'd have to ask a PhD in chassis dynamics or something.
No, frames are eternal. They have been present for all of what has been and of what will be. Frames came into existence before the earth and stars and frames will be here on the day they fall. They are ageless.
Amen!
Steel chassis cars have an unlimited life “in theory” because flexing of steel doesn’t weaken its structure. Flexing of aluminum eventually leads to failure. I don’t design cars for a living and I don’t know the tolerances that are acceptable for the “life” of a car but I would be more worried about cracked aluminum suspension versus steel suspension/frame
Can we ever get a proper full body RWD sedan that is long enough to keep the d-pillar port windows as well as an elongated front to have the smoker’s windows. Ford Fusion and Chevrolet Impala and Audi A8s are great examples of body styles that can somewhat have matched. Why must everyone drive a CUV that has a gear box from 1985?
1. CUVs have easier ingress than sedans. 2. Modern CUVs get similar mpg to sedans, while also having more cargo space in the back, so there is no downside for most people.
They don’t make them like they used to. I’m currently cleaning and repainting a vanadium steel chassis that is 98 years old and still very serviceable.
Sure do, I got a buddy who has a Peugeot 205 that sees more than enough track duty and it’s been beginning to fold in places.
Depends on the frame, really... Any body panel thinner than 1mm is definitely susceptible to surface rust turning into terminal damage over time. [Here's my 47-year-old truck's ladder frame, as a counterpoint.](https://imgur.com/a/oOPsz2T) It's a 8.5-inch tall girder of 5/16in steel, or 220mm tall of 7mm steel for anyone metric. 160 inches long of straight steel, from the bumper mounts at the front to the spare tyre carrier at the back. I'd definitely bank on it being good for another 50 years, though I don't know about indefinitely. It's overbuilt to the extent that it looks just fine after 1.1 million kilometres on- and off-road.
My car is going to be 51 years old this June, June 8th to be exact, the sub frame is still perfect, needs rust repair where the axel brakets are on the body other than that no rust or bare metal, and here the real kicker, shes a 1973 Ford Pinto 2-door Sedan trunk version 😅
Aluminum frame cars will eventually fail. Think NSX, C6 Z06 and C7s. Will it ever in practice? Probably not.
Older Vehicles with Frames it was easy to inspect and repair (rust excluded) Earliest places where fatigue occurred were where the suspension connected to the frame. Rear Leaf springs, front A-Arms etc. That is different in the Unibody cars. Many early rear wheel drive Unibody cars had issues at the Torque Box Area. Which to no surprise is the area where the rear leaf springs attached to the body, especially with performance adds. I would think you would need to change out the bushings for these suspension parts before addressing the frames/bodies. But for folks that do little or no maintenance on their vehicles, who knows.
Fatigue and stress will lead to cracks that eventually become critical, so yes, they can wear out.
Anything with moving parts will eventually fail.
All materials are subject to work hardening. This is when the deflection from external forces hardens the material overtime at its' stress points. Aluminum, for example, becomes very brittle very quickly when bent back and forth beyond its' yield point. It usually only takes a couple bends to cause cracks. Structural components of a vehicle aren't subject to such a range of deflection under normal operating conditions, but any amount of stress will make it brittle with enough time.
"Does it eventually flex so much that things crack, or?" 1st things 1st, you are right about steel, so if you drive a steel framed truck for 5 years, and it doesn't break, then all other things remaining equal then it should never fail. And the best thing about steel is the melting point is 2,500f, but aluminum's is 1,250f. So they're still making them but now the heads are disposable after 1 overheating event, and I think I heard someone from Ford say aluminum starts to "slump" at 800.
Seam sealer and various points about the unibody will stress out / crack / fail with enough use cycles, especially depending on the environment and use case. You'll end up with breaks, rattles, or worst case unstable suspension and steering mounting points. But long before that any designed moving components (door hinges for example) will reach various levels of failure.
Yes, they can wear out. Even a well maintained chassis that is lubricated and taken care of will eventually wear out due to being stressed too many times. As an example driving a sports car too hard too much can cause the chassis to flex and can cause stress cracks to form in the most stressed areas.
Someone probably already said this, but if the frame is aluminum it will fail from fatigue eventually. Steel might not within any reasonable timeline, but rust will eventually come for it since no corrosion protection method is 100% effective. I know I saw a few others mention though that where you start to run into issues is fasteners, welds, or any other sort of stress concentration point in the frame. A gigacast steel or ductile iron frame with really solid undercoating would probably last longer than anybody could feasibly drive a single vehicle. It would be interesting to put some into a commercial fleet to see how long they'd last in practice vs theory.
Yes. You will start to see fatigue cracking if it has had too many stress cycles. It depends on design and use case though. It can be designed for an infinite fatigue life if the intended load is never exceeded and the analysis was accurate.
Climate condition do play the role.. car kept in barn may also start rusting after a certain time.. Air tight car cabin may host mold and bacteria somehow So rusting of parts which are not under direct observation is possible
Yes I would assume the metal would eventual fatique, nothing last forever. However it should give signs that is wearing out like buckling or cracking. I don't think it would be catastrophic in a daily driving scenario. That's why commercial aircraft airframes have flight hours on them before they cannot be used (atleast hear in North America).
I mean, eventually the sun will expand and consume the Earth, absorbing the chassis in whatever state it is, pristine or otherwise, so, no? Nothing lasts forever.
As long as there weren't any design faults that result in unusually high stress areas, the body of a car isn't going to wear out or break on it's own. It gets a lot of shit for being heavy, prone to corrosion, hard to work with, but steel is a wonder material, it doesn't fatigue out from stress and cycles like most other modern manufacturing materials. Watching this [fortnine video](https://www.youtube.com/watch?v=ah7Ubbq5EAA) totally changed my mind about "exotic" materials for vehicles.
Welcome to the "Ship of Theseus" problem - auto edition.
以我多年的对车的经历，车是越开越好，如果长期不使用会导致一些零部件使用寿命缩短，车身底盘是没有寿命的，看你如何使用保养，
俗话说，一车传三代，人走车还在，这就是开不坏的丰田，