Why make radiators out of plastic?

I had a 2000 town and country and the radiator failed. I have a 2008 town and country and the radiator failed last week. And lastly I have a 2000 Mercedes ML320 and the plastic radiator also failed. The plastic develops cracks and the coolant leaks out. How could Chrysler not recall all these radiator failures? AND what idiot would decide that plastic is a good medium to make a radiator out of?

Been in use for a long time by many manufactures.

I have an 89 Mercedes with plastic tanks. I think the 86 of that model had them too. Light weight for emissions and efficiency, cheap, and panned obsolescence are reasons manufactures make that choice. Anytime I can, and its hard on a T&C, I find an aftermarket all aluminum radiator. Often not that expensive, although I will tell you coolant and aluminum don’t always make the best of friends. My current T&C just got another new one (although the 242 mile one hadn’t started to leak but–I rarely put quarter million mile parts back in my car XD)

Back in the early 2000s we were replacing aluminum intakes all the time on GM cars from corrosion. The metallurgy seems to have gotten better as all the aluminum on my 2012 242k town and country looked factory fresh when I recently pulled that motor (the dreaded cylinder 6 misfire), but on a cheap aftermarket all aluminum radiator I would not expect that level. If you do that start doing the coolant flushes at coolant makers recommended mileage that no one ever does.

It’s cheaper to manufacture, and lighter in weight, which improves fuel economy.

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I removed plenty of brass radiators for repair when I worked at a garage. The difference with the new ones is you replace them.

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@StevenAccuosti, you young people really kill me. I assume you are young because those brass and copper radiators of the old days never lasted 12 years. But of course, back then we did not have anti-freeze with the modern corrosion inhibitors that we have today.

I find it odd that you have had so many issues with the plastic cracking. Most modern radiator failures I’ve seen were due to the rubber gasket between the tanks and the cores failing. While this is “repairable” generally the time/labor to replace the gasket is higher than a new radiator.

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Hmm, thanks for the compliment. I have a 50 year old Datsun in my basement garage and it has the original brass radiator. I’ve owned the car for over 20 years. I also find it odd that the only vehicles I ever owned that came with plastic radiators all failed. The 2000 ML320, the 2000 town and country, and a 2008 town and country. The ML320 failed near where the cooling shroud attached. The 2000 town and country failed where the upper radiator hose is clamped on, the coolant inlet split about 2" right up to the tank. On the 2008 town and country near the coolant inlet on the tank itself it split roughly 1" long. I bought a replacement radiator on ebay and ebay says 2,596 sold. Seem to me to be a very high number.

So Chrysler sourced a cheap radiator. If they didn’t practice cost control, no one would be able to afford one of their vans.

My 47 year old truck still has the original brass radiator. I’ve had to replace plastic-radiators in all my other vehicles though, at least once. The good news is that replacing those plastic radiators was a quick and simple job, and the replacement part was pretty cheap. So if replacing the radiator is no big job and a plastic radiator lasts 15-20 years provided the cooling system routine servicing is done on schedule, I’d say the less weight and lower cost for the plastic is a reasonable compromise. I do look for any signs of coolant leaks underneath the Corolla’s plastic radiator as a routine monitoring job every time I pop the hood.

I should mention that a plastic radiator springing a leak can be a symptom of a failing head gasket. Ask me how I know … lol …

I disagree with that particular reasoning

But I do agree that weight savings equals higher fuel economy, and cheaper production costs equals higher profit

So I do agree with some of your reasoning, but not all

Out of the various vehicles I or my family have owned, the aluminum/plastic radiators all lasted at least 10 years. That seems pretty reasonable to me.

I think this talk about sourcing cheap radiators and recalls is a little bit out of line, and not at all realistic in my opinion

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I never noticed much difference in the service life in miles between the brass ones and the plastic/aluminum ones. The brass ones used to cost about 3 times as the aluminum/plastic when adjusted for inflation. There used to be a good radiator shop near me that would recore plastic radiators using the factory plastic parts which gave you a better radiator than the cheap offshore ones for about 80 % of the price. They had to stop when the offshore ones becam cheaper than the rebuilts.

The brass ones did last longer on little used vehicles. Plastic ages with time much more than brass.

All three of my plastic radiators did not fail at the core… it was the plastic tanks that cracked. I service all my vehicles on schedule so I guess that kept the aluminum from deteriorating. It didn’t do anything for the plastic though.

Main reason is that injection molded plastic is much cheaper and cost is what drives everything.

At least with the old brass radiators a bit of silver solder and torch made it cheap and easy to fix. And of course brass is pricey.
Someone broke into the building at a local scrapyard here a few years ago and stole 3 or 4 containers of scrap brass. They cut a hole in the side of the building. Loss was somewhere around 50 grand.,

Isn’t brass just a combo of copper and zinc? It must be the copper that makes it expensive. I purchased some copper 3/4 inch fittings at the hardware store the other day, and boy are they expensive. A brass valve, copper slip to threads adapter, copper union, and a 1 inch nipple cost nearly $30.

Yes, brass is copper and zinc with some aluminum, lead, or arsenic throw in now and then to improve corrosion resistance and make it easier to machine.

I went into a store in Tulsa a few years ago to buy a piece of brass round stock so I could machine some Harley engine bushings and they must have had 3 or 4 semi loads of brass stock in there. Some of it was 4" by 20 foot long. I can’t even imagine the value of the stock on hand.

Yup. My 84 GMC pickup had a a plastic radiator…or at least parts of it were plastic.

This guy on Ebay has sold over 2660 T&C radiators for models 2008-2016. I checked his sales history and he is selling 3 to 6 every single day. I would say that indicates Chrysler problem. Here is the link.