It has been real cold here (15 and below) . Both of the hoses on my radiator leak when the truck sits over night and I start it up in the freezing morning. I think the extreme cold ( below zeros) causes the hoses to shrink and when I start it and it warms up the hoses expand causing them to leak. But I don't understand why because they don't leak in normal temperatures. I have 2 hose clamps on the bottom that are cranked as tight as they can be without stripping, and one hose clamp on the top right hose that also leaks. I took the factory junk hose clamps off and replaced with the screw tightening kind. Is there any better hose clamps I can use or just put more on it? Maybe some new hoses? Truck has 159k miles. This is the third time they leaked and I checked the clamps and they are tight

 

Replace the hoses AND the clamps. They shouldn't leak, regardless of weather. When you install new hoses, and tighten the clamps, they WILL loosen up a bit at first, just re-tighten them, and you should be golden.

 

The problem is the part I put in bold. The factory tension clamps are not junk clamps, and it's a shame so many people repeat such a misstatement.

Examine the neck of the radiator and note that it's made of plastic. Plastic is liable to break when met with excessive force, especially when that force is a squeezing, crushing force. What happens when people replace the tension hose clamps with the screw clamps is they apply too much torque and end up cracking the plastic radiator inlet. The tension clamps apply the correct amount of pressure to prevent the hoses from slipping off but not so much that the plastic parts will be damaged.

Check the radiator inlet and outlet for damage. You may be in for more of a repair than you imagined.

And for the record, I have over 200K miles on my truck using the tension clamps and never a leak.

Sorry, but I'm going to disagree with you advising the OP to get new clamps and to tighten them. The OP needs to install the correct clamps for his application.

 

The spring clamps were initially used not because they were better, but, because they were CHEAPER. Screw clamps are just as "correct" as the spring clamps. I like the screw clamps better because they are a bit more 're-useable' than the spring clamps. I have had trouble with get the spring guys to re-seal, never a problem with the screw clamps.

Screw clamps need to be re-torqued on occasion, as they are set pressure. as the hose ages, the clamp will leave a lasting impression on it, the spring clamps are constant pressure, and while they dig in, they are still applying some pressure to seal the hose.

Either will work just as well. (new vs. new)

Yes, it IS possible to overtighten screw clamps, but, you actually have to be TRYING to do so, to accomplish that. I have never damaged a fitting with a screw clamp.

 

Sorry, but that's not correct. The tension clamps started with the imports as they were the first to start using plastic components with the radiators. The tension clamps are used for the reasons I stated. It also helps that their simplicity speeds installation on the production line. Like I said, people have a tendency to apply too much torque to the screw style clamps because they believe some type of feedback (meaning that point of resistance) should be reached. By that time they have unknowingly cracked the radiator inlet/outlet and then scream about "junky parts".

If they wear out then they should be replaced. Think of the serpentine tensioner. How many people actually replace them when the engine has logged over 100K miles? Not many, and I admit that I am guilty of this, but yet there is a recommendation to replace them after a certain point as they lose tension and can cause belt damage or premature wear.

To call them "factory junk" is ignorant.

 

Thanks for the insights guys. but I still believe the factory hose clamps are junk. not to start (or join) an argument here but Just because they are factory doesn't mean they are better or perform the job the best. Look at the factory dash and plenum problems. They have problems but still use these cuz its cheap and gets the truck sold and maybe last until warranty is up. But like I said I'm willing to try anything to get these hoses to stop leaking when its this cold out, even if I have to try putting the factory clamps back on. Can anyone explain the physics of why this happens only in extreme low temps close to and below 0? Is it because of expansion/contraction when it gets warmed up? It doesn't leak any other time, besides temperatures that around 15 and below.

 

Don't recall calling them junk.... I just don't like them. They work. And that's all the manufacturers care about.

Started on imports: Irrelevant.
simplicity: reduced production cost of the clamp. (cheaper)
speeds installation: reduces production costs of the car. (cheaper)

Plastic or brass, doesn't really matter either, as improperly installed, you can trash the brass radiators with screw clamps as well. (not entirely sure which is easier to crush..... I have never had a problem with screw clamps.) The key word there being "improperly". Yeah, if you torque it down with an air tool, or anything more than a quarter inch ratchet, you can break parts. 99% of the time though, the clamp itself will break, before the part you are clamping to does.

 

I pointed a friend of mine to this thread as he lives in Canada and knows cold weather all too well.

He agrees, that the band clamps are not at fault and stated that it is common for the appearance of leakage to appear in temps around -30ºC (-22ºF) no matter what style clamps are used.

 

I bet most here have never SEEN a brass radiator!

 

Just to add my $.02, I have a new rad. new hoses, 145,000 miles and factory hose clamps with no leaks. I havent had a problem with them on any car. No problems with the worm clamps either though.