So I'm trying to track down why my cooling system is so inefficient, and I've arrived at the point where we test the radiator. After letting it get up to operating temp for a bit, I measured the temperature with an infrared thermometer, and the results were not encouraging. My readings were about 150 at the top, and about 100 4-5 inches below that. So, my questions for you guys:

1) Was I measuring correctly? I tried to get it perpendicular, but it was difficult to get a good reading at the very bottom. Dunno how much this matters.

2) Does this mean the radiator is clogged or could there be some other explanation?

3) Does anyone have a recommendation for a radiator replacement? This one from the label is a 2016 Nissens; I'd like the next one to last a little longer.

 

Best4x4 recommended the $60 one on ebay, and so far so good(no leaks, but very little run time). It looks identical to the stock one I removed too.
My truck wasn't overheating either(just had already replaced the rest of the cooling system), and the old one must have weighed 10 lbs more than the new one.
As said, they looked identical, so I wonder how much sludge was stuck in my old one.

 

Thanks. Do you have a link to the ebay radiator?

 

Does the truck overheat when idling? If not, it probably is not your radiator. If it does, try running a garden hose over the radiator, if that keeps it running cool then it likely is the radiator.

 

It's pretty much living at 212 whenever it's not moving, and that's in the winter. I'm fairly sure it'll start overheating once the summer begins.

 

Do the garden hose test, if it is still at 212 it is probably a stuck thermostat. If it comes down with the garden hose it is the radiator. I never run factory style thermostats on my discos.

 

I will admit that B4x4 knows alot more about these than I do but I get real paranoid about the cooling system. If you got 100k plus miles just accept that the radiator needs changing. I go with the nissens unit so I can sleep at night. With that said, 60 bucks is one hell of a deal but they are made from chineseum.

 

I replaced the thermostat with a 180 degree version before I parked it. I'll try the garden hose; I know the inline thermostat mod is ultimately the best option from a longevity standpoint, but I'd really rather not go that route unless I have to.

 

You need to go that route. Trust me on this one. It is the first thing I do to any truck. Always use a motorad thermo cuz they are good. You don't need to cut your shroud. Whole project takes about 30 minutes.

 

That's... fair. I'm going to go ahead and assemble a parts list.

I would really like to save this radiator though; there's no reason I should have to throw out a 4 year old Nissens. Would it be possible to remove it from the vehicle, fill it with some sort of radiator flush chemical (suggestions wanted) and then backflush it with a garden hose?