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Comment by greenthrow | Hacker News Reader

The body panels are more and more often plastic or aluminum these days. There's still often steel in the suspension and subframe, though.

The point of the article, though, is lots of people still spread FUD a out EV batteries and the data we have shows that batteries are not a problem. They last longer than transmissions and engines on average.

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I've noticed so many "common knowledge" things being anchored into the past, especially as I age - and especially for vehicles.

The "rotting frames and body panels" thing was certainly common where I'm from when I grew up, but these days it's very normal to see 20+ year cars on the road with very little salt related damage. I have a 2007 Acura MDX that is stored outside for the past 8 years, never washed by my parents who I gifted it to, and driven through some of the worst winter road conditions possible. Visiting in the winter you'd think it was a grey vehicle (it's black) from all the salt spray adhered to it which stays on until it's driven in the rain come springtime.

It shows utterly zero frame or body rust even today. I expect the rubber seals and such to fail before anything else. This is pretty much the norm.

Cars are not made like they were in the 1980's and 90's any more. The coatings and type of materials are vastly different and improved. There are certainly models out there that have problems and you can get unlucky, but it's no longer a rule of thumb.

It's not just vehicles though. It's pretty much endemic to all things. People get anchored to their "formative years" and then never update their priors. I assume it takes a generation or two for such things to die off and the "common knowledge" to be updated. EV battery tech will be one of these things - we will be anchored to the common tropes that were true for first and second generation vehicles but no longer are for quite a long time.

It persists because incompetently-managed cities and their sycophants need a convenient scapegoat for why they can't properly clean roads in the winter.

While I suspect you’re right about newer cars because of galvanized steel etc, but I also wonder how much of the contrarian viewpoint is due to sampling bias. Maybe your Acura was just good luck? I’ve had a domestic wagon of similar vintage that went through many Midwest winters. The exhaust rusted off and so did the sub-frame leading me to offload it many years ago. We really need better data than our personal anecdotes to understand the problem.

Definitely need more than anecdote. Exhaust system though is a wear item, I'd expect to replace that every decade or so.

Sub-frame, not so much!

A quick google shows graphs for "Average age of the US used car fleet" to be around 6 years in 1975, and increasing to 12 years today. Not enough time today before family arrives to really dig further though.

Very true, and car longevity has been steadily increasing. Although, I don’t think the bulk of them failures are attributable to “rotting body panels”. I remember when a car with 100k miles was considered essentially dead, whereas more drive trains routinely last twice that long.

On the other hand, I drove my 2009 Toyota Corolla in upstate NY for 10 years until the exhaust system literally fell out of it on the highway.

There was very little visible rust on the body.

(To be clear, if I didn't need more space inside nowadays I would absolutely be delighted to get another Corolla; I think it's a trooper for making it 10 years in this weather. I also replaced the exhaust system and then sold the car for significantly more than the repair cost to someone who wasn't planning on keeping it in quite a snowy climate.)

Many modern vehicles experience galvanic corrosion at dissimilar metal junction points at accelerated rates in the presence of salt.

A bigger issue I'm seeing is ordinary corrosion at metal-plastic interfaces where the magic coatings which keep the rust at bay get worn through due to vibration and dissimilar thermal coefficients. Another such problem sometimes occur when windows are not mounted with enough of a gap between the glass and the surrounding metal, again leading to the coating being worn through due to vibration and such. Look for the former problem at wheel wells, the latter at the bottom edge of rear windows.

Ah this might be an in-industry definitions thing[1], I was taught most anything thin, especially the pieces that are welded to the unibody, are panels. Not just the outer skin. So floor pan, pillars, trunk panels, roof, subframe, maybe control arms, etc are all panels. Basically anything stamped out of sheet metal. It is the way they're often constructed that leads to corrosion, thin pieces of metal in close parallel proximity are especially hard to clean. Think two flat pieces spot welded together one on top of one another as many seams are. I'm sure capillary action doesn't help those either. They'd have to be sealed in paint or epoxy entirely to avoid the seam corroding. Welding itself changes the structure of the steel and leads to corrosion near the weld. If not spot welded, a different steel might be used for the weld that has higher strength to compensate for welds weakening the steel - but to get that they trade-off higher carbon content, making it more prone to corrosion.

There are very few all-aluminum cars. Audi A8 was for a while and might still be. I am not aware of anything cheaper.

[1] https://automotivedictionary.org/dictionary-of-automotive-te...

Not lasting forever but car bodies are fully submersed during the painting process and should seal many of the areas you mentioned for a good time.

You're right that there's more parts that don't rust on modern vehicles. However, newer vehicles tend to be unibody compared to the older body-on-frame. When it comes to salty corrosion, parts sandwiched together often create places for the saltwater to be trapped, making the problem worse.

The more I look at newer cars, the more I tend to believe that they will last exactly as long as the warranty, then disintegrate into repair hell.

My theory here is that in the past many things have been over engineered or designed. Now all this fat is being optimized out and the weak spots are showing. But there is still a delay between the engineering change and the weak spots emerging.

The nostalgia based belief that "things were better before" is generally not supported by the facts. Cars in the past were much less reliable than they are today. This goes for most consumer products. That doesn't mean there aren't problems today that should be addressed, but the golden times of the past are largely imaginary.

Well luckily we don't have to go on vibes and there's data that shows modern cars last longer than older ones, on average.

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