What does that have to do with plastic parts?
AMC cars of the late 50s through at least mid-60s didn't look as goofy as a lot of other American cars, in my opinion.
Are Plastic Parts a Problem?
- Thread starter Shel_B
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AMC cars of the late 50s through at least mid-60s didn't look as goofy as a lot of other American cars, in my opinion.
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Just working from memory...it's not what it used to be.
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Those years were well before they went out of business (as I remember). Think Pacer. Gremlin. etc.
Car seats are plastic and so are motorcycle helmets. I guess those pieces of plastic junk cannot be trusted either. Oh wait, those are fine? No complaints had there? Well, that make sense. I mean we can all certainly agree our engine’s components are infinitely more important than our children and brains. Carry on.
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I think you have best described what purchaser expectations and perceptions are, versus engineering specs.
Some people expect cars to last forever, (ie, plastic parts included). Other people expect to have parts replaced and are not "insulted" when it happens. Helmets have a defined lifespan and a required replacement date. Same with aramid fiber bullet resistant vests.
It's all about perceptions and expectations. I doubt "wizard" would have a problem with replacing his motorcycle helmet, or a timing belt, etc. at the manufacturer's recommended interval. His issue is he thinks a water pump should last "forever". He is wrong - and he makes money on his videos.
We are increasing his views by discussing this here and I suspect that is exactly what he wants. More views equals more advertisement dollars.
That’s a Bingo!
Precisely! It doesn’t matter to him if his opinion is correct or not, what matter is that it generates traffic. And controversial opinions bring in the views, cough, Scotty, cough…
twouvakind
Site Donor 2024
Steel timing gear (cam) with nylon teeth, traditional steel chain. Guess the outcome.
Ford Winstar van about 20 years ago with a nylon gear in the AT it was the first thing to fail after only a few years.
Costly fix.
Costly fix.
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Most plastic car seats with the exception of MB Tex and BMW SensaTec are terrible and yes total junk. MC helmets can be real crap if they are polycarbonate and seamed in the middle, the good ones are one piece carbon kevlar composites.
4WD
$50 site donor 2024
I’m booked transatlantic in a few days - dang it - on a cheap plastic B789 - wish me luck
Obligatory reference to an aluminum aftermarket replacement valve cover:
zzperformance.com
Sonic/Cruze 1.4T Aluminum Valve Cover
Replace your stock plastic valve cover with this full aluminum valve cover for your LUV/LUJ engine. Valve cover comes with new gasket, new bolts, and a full new PCV assembly. Silver in color, not bare aluminum. Internal PCV plate bolts Loctite-ed. The valve cover PCV is a common wear/failure...
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There are plenty of junk metal components as well. Quality matters in either case.
I want some automotive examples of things that used to be (or OEM part was) metal but were made more reliable by switching to plastic. It seems like switching to plastic can save weight and cost but repair costs are now expensive enough to swamp those savings.
Undercarriage skid plate and other covers perhaps, but IMO for the most part there were other reasons to switch and reliability was merely deemed "good enough" by a manufacturer who expected it to outlast the warranty on that subsystem.
Undercarriage skid plate and other covers perhaps, but IMO for the most part there were other reasons to switch and reliability was merely deemed "good enough" by a manufacturer who expected it to outlast the warranty on that subsystem.
I don’t look at it this way. Maybe if you assume all plastic parts will fail then I can see the worry, but the opposite is true.
A vehicle is a sum of all parts and we all know all vehicles end up at the scrapyard in the end. Some due to rust, some due to engine or transmission failure, some due to an accident etc.
A truly used up vehicle in an ideal world would simply fall apart the moment you drive it to the scrapyard or a recycler. To me at least it would be ideal because that would mean I extracted the maximum value and life out of it.
But cars are scrapped with pretty much majority of their components still in working condition.
So what good is the metal part for when the vehicle is at the end of its life?
That is the reason vehicles up to the 80s got such a poor fuel economy. You had to drag all that metal around and then it went to the scrap yard anyways.
Plastics, or rather composites, are part of the reason we can enjoy powerful vehicles today that get exceptionally good fuel economy, compared to the “good old days” .
^ What good the metal part is at end of life is that it didn't fail prematurely so you had no additional cost to replace it. That is the problem with the plastic parts with shorter lifespans, many of which have.
It is not why '80s vehicles had poor fuel economy. Many vehicles today have as much weight, like an '85 Buick sedan weighed about as much as a 2023 Camry today, yet the camry is a smaller size class.
They get better fuel economy mostly due to engine, then transmission, then aerodynamics. Replacing several of the plastic parts that fail with metal ones would only account for a few hundred lbs. (or less) difference in many cases. Remember, metal doesn't HAVE to be steel. There's plenty of good aluminum cast or machined parts that I'd take over plastic, especially in areas that heat up or are subject to pressure charges like a radiator, thermostat housing, intake manifold. These are all parts that I've had to replace on various vehicles.
It is not why '80s vehicles had poor fuel economy. Many vehicles today have as much weight, like an '85 Buick sedan weighed about as much as a 2023 Camry today, yet the camry is a smaller size class.
They get better fuel economy mostly due to engine, then transmission, then aerodynamics. Replacing several of the plastic parts that fail with metal ones would only account for a few hundred lbs. (or less) difference in many cases. Remember, metal doesn't HAVE to be steel. There's plenty of good aluminum cast or machined parts that I'd take over plastic, especially in areas that heat up or are subject to pressure charges like a radiator, thermostat housing, intake manifold. These are all parts that I've had to replace on various vehicles.
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