Thanks. I'm off to Auto Zone first thing this morning.

Changing the radiator cap pressure does raise the question: I wonder how low is "too low" ? I can remember when a 7 lb. radiator cap was pretty standard. Now cars back then ran 170-180º thermostats - and over 210º was considered as "overheating" - but this Jeep does not run hot. I wonder what would happen if I used a 5-6-7 lb. radiator cap? <g>

PHM
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I think 14 is about as low as you want to go on these. A certain amount of minimum pressure does indeed help raise the boiling temperature a bit to help prevent overheating and like you say these do run quite warm already as a norm. But when they started this high pressure system trend radiators were still all metal and able to stand higher pressures better than these plastic radiators. Just imagine how much these are "ballooning" and contracting back every heat up to pressure cool back down cycle. It's a wonder they even last two or three cycles in the first place. lol

Something else to remember... Those guys at the store are in the business of selling radiators. lol

Yes; but with a lifetime warranty on them it seems counter productive to their best interests to have the radiators repeatedly fail. <g>

PHM
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The engine is fairly new and runs cool and the antifreeze always looks pristine - if that is any indication of flush-requirements.

But when you say: "maybe water pump issue" - do you mean that a problem with the pump could possibly be resulting in excess cooling system pressure?

It's an interesting possibility but it's not really that kind of pump - it's a circulating-type pump rather than a pressure-developing pump.

Do you have any direct knowledge that the water pump could be overpowering the system? I can tell you that the radiator originally blew out right after the water pump was replaced. <g>

PHM
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One might think so... but this isn't quite how it works. Having a much higher pressure cap listed as the replacement on models where it is truly not needed blows up twenty times more radiators that are not yet under warranty first.

They make a replacement profit off of everyone of these that might not have blown up. Then they don't personally foot the bill on the warranty, the maker of the radiator does. So it is a win win for the part houses to sell caps that blow up radiators.

I have worked in part stores and this is a constant battle between the part manufacturers and the retail stores who offer the warranties.

Can you expand on that concept for me please? How would the radiator have to be mounted incorrectly in order to create a failure scenario? It makes sense if you picture a distortion of the radiator's structure - inducing a 'twist' or something like that.

I would like to mention that in both cases the radiator failure occurred right after the radiator was re-installed. <g> Although . . . I do treat the SOB's like fragile eggs whenever I am handing/dealing with them. <g>

On counter-point: the radiator install / mounting is very straight forward. Two insert/locator pins at the bottom, the top locating bracket with it's four 10mm bolts and two nuts, and the u-brackets in front of the condenser. Then the shroud is located to the radiator with two small locating widgets at the bottom of the radiator core and two 10mm bolts horizontally through side tabs with clip-nuts.

But . . . . Suppose something in the front of the truck is distorted? Some un-noticeable mis-alignment between the various attachment points? It's not as though the radiator bolts down to a flat surface.

What was in your mind when you wrote this: "radiator not mounted correctly" ?

PHM
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