Just wondering what causes the upper radiator and hose to get hot to the touch yet the bottom of the radiator and lower hose is cool to the touch where you can just leave your hand there a while and it's cold after driving home from anywhere really 30 min plus drive.

 

Your radiator may be clogged up. I'm not sure what radiator shops do these days as far as boiling them out or rodding. Is it aluminum or copper?

 

Well that's not good and who knows how long that's been that way. The guy I bought it from 3 yrs ago said he changed the water pump.

Then this past year I saw a leak around the thermostat so I pulled the housing removed sealant he put on it and replaced the housing using no sealant just gasket no leaks.

Is it possible to flush the radiator. The truck would overheat if the pump wasn't installed correctly I'd think.

 

I'm not so sure you have an issue with your radiator. Several guys have reported the exact same thing and were concerned about only to find that everything was just fine. The radiators in these trucks are overkill and they really cool the coolant off A LOT. if you're not seeing higher than normal temperatures on your gauge, I wouldn't worry about it. And definitely DO NOT add any flush additives or coolant system cleaners to your truck. These are very good at one thing and that is making your injector cup seals leak...

 

Seems to me this means your fan and radiator are cooling things down well. I believe i would take a look at thw fan clutch though. If it sticks, the fan will run all the time, cooling too much

 

I'll throw the IR thermometer on mine after I get it up to operating temps. I've never checked mine.

 

Well here is what I came up with.

Radiator at the top: 171 Middle: 96 Bottom: 86

Tank (plastic) top: 141 Bottom: 96

Upper rad hose: 171 Lower: 143

Upper stat housing: 204 Lower: 194

 

The upper hose is hot because the coolant is coming out of the hot engine. As the coolant flows down through the radiator tubes it gets cooled by the air flow through the fins. Cold coolant returns through the bottom hose. Your radiator is doing its job.

 

Well I'm going to respectfully disagree with everyone who thinks the PO's issue is normal. I'm outta this one.

 

Don't leave us!! No seriously, if you disagree, please explain why. That's what makes this site so valuable is that we all have different experiences with these trucks. My thought was that seeing cool water at the bottomw hose would mean that it is doing its job. Seeing hot water at both hoses would tend to indicate that the radiator wasn't cooling the water very well. I just thought that the temp gauge would show that things were getting hot if the radiator wasn't working. There was a thread on this a few months back. Let me see if I can dig it up.

 

THIS is the one I was thinking of. I see you posted in this one too Pete. I guess he didn't post his resolution in this thread though.

 

Isn't that what a radiator is supposed to do? Cool the engine coolant? If the water coming out was the same temperature as the water going in, you could just remove the radiator and run a hose from the upper to lower and be done with it.

In cold ambient temperatures with an unloaded truck the radiator is WAY oversized for the cooling that's needed. The radiator is sized for full throttle, maximum load, going up a grade in a 115°F ambient temperature. In those conditions the temperature difference between the upper and lower hoses may only be 15°F. With much colder air temperature the radiator is MUCH more efficient at cooling the water. So much so that the lower hose if often going to be within a couple degrees of the ambient air temperature.

If the truck isn't overheating I suspect there is nothing wrong here.