Failed radiator at 48k

Your old coolant just lost it's shelf life. No need for a new radiator - trust me, I have 3 jeeps :)

1. Buy the coolant per your jeep specs. (HOAT / OAT)
2. Drain the entire coolant and flush it good.
3. Refill it with a new fresh coolant.
4. Burp it properly and get air pockets out.

You just saved lots of $$$
 
I find it hard to believe that a radiator with that many miles on it is plugged up. What year is the JK?

Is your cooling fan coming on when it's supposed to?
 
I find it hard to believe it's the radiator as well.

Did they pressure test the radiator to confirm it's leaking? Have you inspected the color and condition of the coolant?
 
If it's leaking at the radiator it should be easy to see, my radiator had a leak and found it was just the radiator cap was bad. Put a new one on and no more leak.
 
A radiator will only fail if there is a "plugged and/or leaky" tubes.
If the fluid is flowing thru the tubes there is no way the rad will fail unless the outer fins are caked-up with dirt mud.
Dirt/mud: the mud prevents air flow thru the fins to cool the tubes while in motion.
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recognizing this as an older thread, My wifes 2015 JKU was loosing fluid from what turned out to be a bad weld in the radiator. I could smell the fluid during trips. Problem resolved by installing a new radiator. that was at about 48-50K miles.
Now at about 68K miles the engine light came on and the obd reader provided a cooling issue. I checked the fluid level and found oil in the radiator. I will call my the mechanic who installed this item and ask if lubricants were injected to the fluid. this is done for home heating / hydronic systems to add lubricity to the pumps. In the meantime the oil was down 1qt and when i added oil the engine light went off. HMMMMMM wrong msg.
If someone recognizes this scenario could you share your thoughts or direct me to a more recent post. Thanks in advance
 
Just to make sure i understand.
1 your Jeep has oil in the Coolant/radiator , I’m assuming you opened the radiator cap and the oil had floated. They don’t inject Oil into the radiator coolant, I don’t mean to be rude, but that made me laugh, I wouldn’t tell my mechanic that, he’ll think less of you.
2 Your oil was a quart low?

Well, your Jeep, I would guess, is in for some Major work. Cracked head most likely (but I normally hear coolant in the oil). You had a coolant leak, so your cooling system was compromised. The engine was running hotter than it should, and problems happen from that.
If you have oil in your coolant, means there is a crack or serious malfunction and one system (oil) has connected incorrectly to the coolant system. That’s usually big dollars and work to fix.

The 1st problem, I would guess, caused the second. Running hot cause it, they fixed the radiator, but the next problem was caused. I wouldn’t think it was the mechanics fault. if you’re lucky it’s a gasket failure and not a crack.
 
I thought this JK radiator thing was a known problem. Something to do with sand residue in the head castings settling in the radiator causing premature failure. My radiator leaked at 31k (warranty to 30 🤣 )