Radiator: OEM style auto vs. OEM style manual vs. high end aluminum (done right)

I was at a trade show a representative from a large aftermarket aluminum radiator company (starts with m) told me there Jeep Wrangler radiators have a high fail rate because the core support actually flexes causing stress on radiator My personality don’t see how that is happening. Just passing on the info
 
Davidtj said:
I was at a trade show a representative from a large aftermarket aluminum radiator company (starts with m) told me there Jeep Wrangler radiators have a high fail rate because the core support actually flexes causing stress on radiator My personality don’t see how that is happening. Just passing on the info
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I see that mentioned as the cause quite often. They are full of shit. It is very easy to tell they are full of shit if you are capable of any critical thought.

1- examine any grill shell out of the vehicle and it becomes apparent that the design is exceptionally rigid. Adding to that rigidity is the V bar that is in there. The front face has a lot of stiffness built in with the way the slots are made. The V bar adds some to hold the back edges apart dimensionally and prevent racking.
2- examine any OEM TJ radiator and look at how the mounting flanges are designed and then attached to the radiator. You will discover that the whole mess full of coolant is attached to the two plastic end tanks with very small #10 machine screws, 2 at the top and bottom and the nuts are just in slots molded into the ends of the tanks. There are a lot of things you can call that, robust is not anywhere on that list.
3- examine the mounting flanges themselves. They are fairly long extending from the sides of the radiator over to the grill shell. That bit of flex absorbs any fore and aft forces and stops the flanges from being ripped off the sides of the radiator. The rigidity of the grill shells eliminates any other twisting of racking motions that protect the radiator.
 
So why do they fail so often? I have had CJs that were beat to shit before I got them. And beat even harder after. In the 18-20 CJs I've personally had i only encountered 1 radiator failure. And that was due to a small sapling getting punched through the grill and past the block. I can't recall any YJ rad issues either, but I personally never owned but 1 of them. Of the (iirc) 2 XJs I've had, 1 crapped out. This is my first TJ, yet I see radiator and/and/or cooling problems constantly coming up. Tons of other makes and models use a plastic and aluminum core yet they seem to rarely fail. So why TJs? And why do aluminum radiators (which are an upgrade on every other vehicle) have such a high fail rate?
I have a 52 Dodge still on its original radiator. I know because my grandfather bought it with under 10 miles on it.
Driven hard? Most agricultural and industrial equipment would LOVE to be pampered the way TJs are, and yet they keep going. So why do they fail? Most any 20 year old vehicle still has original radiator.
 
Goatman said:
So why do they fail so often? I have had CJs that were beat to shit before I got them. And beat even harder after. In the 18-20 CJs I've personally had i only encountered 1 radiator failure. And that was due to a small sapling getting punched through the grill and past the block. I can't recall any YJ rad issues either, but I personally never owned but 1 of them. Of the (iirc) 2 XJs I've had, 1 crapped out. This is my first TJ, yet I see radiator and/and/or cooling problems constantly coming up. Tons of other makes and models use a plastic and aluminum core yet they seem to rarely fail. So why TJs? And why do aluminum radiators (which are an upgrade on every other vehicle) have such a high fail rate?
I have a 52 Dodge still on its original radiator. I know because my grandfather bought it with under 10 miles on it.
Driven hard? Most agricultural and industrial equipment would LOVE to be pampered the way TJs are, and yet they keep going. So why do they fail? Most any 20 year old vehicle still has original radiator.
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One of the reasons they fail so often is the tank design to get it under the hood. The upper hose inlet points right at the back wall of the tank and a large flat surface above it. Steam is very bad and any over heat situation that produces steam will erode the inner wall and weaken it. Then there is the design of the tank with that flat top. It would last much longer if it was a full radius like a half pipe and that would stop the flexing of the flat surface which is where we see a lot of splits.

If they were to increase the tank wall thickness slightly, change over to a half pipe design with ribs across it, I suspect that radiator life would double since we rarely see core failure.
 
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For what it's worth Mishimoto makes radiators for a lot of vehicles. Back when I was into BMWs and even racing Miatas, they still had the same reputation that they do with Jeeps. That they make aluminum radiators that last a year or so and then start to leak.

However, somehow they continue to sell them. For some reason people have it in their head that they really need an all aluminum radiator :LOL:
 
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We just had this debate in another thread..
And I have been using aluminum radiatiors in street cars for 15+ years without any issues. At first I thought that maybe there are just no good MFG's for the Jeep, but that doesn't make much sense. I have installed some cheap ass radiators into fast-n-furious Honda's that haven't died yet.
Then after reading through this someone brought up a good point. The Jeep has a pretty rough ride that jars the radiator around, perhaps the split case design is actually helping to reduce stress in the radiator. What if.... They had a split case radiator with aluminum caps? I wonder if this would solve both issues. 🤔
 
If YJ and CJ radiators don't have this rate of failure, how hard would it be to do a retrofit? I know given a torch and a welder anything is possible, but in the real world would it be reasonably possible?
 
Zorba said:
There are people in this thread congratulating themselves on getting 10 years out of a radiator - if that happened to me, I'd be beyond pissed off.
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~$250 part every 10 years?

:unsure:

not "beyond pissed off" worthy

😉
 
mrblaine said:
One of the reasons they fail so often is the tank design to get it under the hood. The upper hose inlet points right at the back wall of the tank and a large flat surface above it. Steam is very bad and any over heat situation that produces steam will erode the inner wall and weaken it. Then there is the design of the tank with that flat top. It would last much longer if it was a full radius like a half pipe and that would stop the flexing of the flat surface which is where we see a lot of splits.

If they were to increase the tank wall thickness slightly, change over to a half pipe design with ribs across it, I suspect that radiator life would double since we rarely see core failure.
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Probably the best failure scenario I have heard, guess that's why submarines are not square.
 
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L J said:
~$250 part every 10 years?

:unsure:

not "beyond pissed off" worthy

😉
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Oh yea it is. Because it shouldn't fail that often: NO OTHER VEHICLE HAS THIS PROBLEM (apparently). There's something wrong here. Settling for 10 year service life from something that should last AT LEAST 20 is unacceptable.

I wonder if the notorious Jeep "heat soak" contributes as well. Dunno - just throwing the idea out there.
 
mrblaine said:
One of the reasons they fail so often is the tank design to get it under the hood. The upper hose inlet points right at the back wall of the tank and a large flat surface above it. Steam is very bad and any over heat situation that produces steam will erode the inner wall and weaken it. Then there is the design of the tank with that flat top. It would last much longer if it was a full radius like a half pipe and that would stop the flexing of the flat surface which is where we see a lot of splits.

If they were to increase the tank wall thickness slightly, change over to a half pipe design with ribs across it, I suspect that radiator life would double since we rarely see core failure.
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So mopar plastic is better at resisting damage from high pressure steam that aluminum?

Hmm...

What if the aluminum radiator inlet is a removable piece of cast brass or billet aluminum that bolts onto the top tank?

It would be interesting to test a modification to a mishimoto.

Also, be interesting to try out coating the tanks in a heat conducting epoxy finish.

Radiator changes are a pain in the ass tho.
 
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WallyWest said:
Not yet, but Mopar will discontinue them at some point. Then what?
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Buy one now and put it on the shelf? Worry about the next decade if and when ...

Zorba said:
Oh yea it is.
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nope

~$250 in 10 years. Anyone that owns, and uses, a TJ easily pisses away more than that in a year.

just nope

Zorba said:
Settling for 10 year service life from something that should last AT LEAST 20 is unacceptable.
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We don't have to settle. We could sell the Jeep.

Zorba said:
I wonder if the notorious Jeep "heat soak" contributes as well. Dunno - just throwing the idea out there.
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Quite possibly. I'm not a materials engineer though so I'll have to leave that to others.
 
Yea, you can always sell the Jeep.

Still not acceptable. I "may" be needing a new one myself soon, but I'm going to turn over every stone before I accept mediocrity.
 
WallyWest said:
Not yet, but Mopar will discontinue them at some point. Then what?
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'

Im just past a year mark on my Napa radiator, twice the life at this point of the Denso ones I've had before. So we will see but it does seem that Napa products are a little better built then other parts house brands.
 
Brian83 said:
'

Im just past a year mark on my Napa radiator, twice the life at this point of the Denso ones I've had before. So we will see but it does seem that Napa products are a little better built then other parts house brands.
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Ha is there a way to set reminders through the forum. I want to update at a year on my Murray's water pump and radiator (unless they crap out sooner)
 
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From what I've come to understand, it's not that a high end aluminum radiator (one that doesn't leak) can't be built for a TJ. It's that in doing so, the end result would be a $1000 radiator (just a guess), which is more than most would spend.

In addition, the TJ market simply isn't big enough for a larger company (with the manufacturing facilities and tooling) to want to pursue.

That's my guess at least.
 
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Zorba said:
If YJ and CJ radiators don't have this rate of failure, how hard would it be to do a retrofit? I know given a torch and a welder anything is possible, but in the real world would it be reasonably possible?
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Brian83 said:
Im not in the market for a radiator but has anyone ran a Copper and Brass radiator from CSF? They are $350. http://csfimports.com/copper-brass-radiators/
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I run a YJ copper radiator in mine. It bolts right in. That being said I am not sure I would not run this with the 4.0 as it is not as effecient as the aluminum one and could induce overheating issues. Not a problem with my 2.5.
 
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