Well, I got lucky... or unlucky. Depending on how you look at it.

I got lucky because there is not head gasket or other problem with my engine.

I got unlucky because the only problem with my truck WAS a leaking radiator. Apparently, an undetected leaky radiator will introduce air into your cooling system, and air causes DexCool to turn into the sludge I found, that looks like oil and water mixed. The mechanic called me with the diagnosis and, of course, I had to check it out online and sure enough, I found many sites saying the same thing.

Double unlucky... this is the second radiator with the 'H3 crack' at the top. I had the factory radiator rebuilt with new caps just over three years ago. So that design flaw we have all talked about appears to be in the truck and not just the radiator. If you go back with the same design, it will crack again. I may think about having an aluminum radiator built that mounts differently.

So, I am in for an $1100 repair due to a leaky radiator and DexCool. I know some folks swear by DexCool, but if I had been running regular anti-freeze I would only be worrying about a leaky radiator right now. But as it is, I have to go through all the flushing and all that. I will be going back with regular anti-freeze. So, I have to change it in 3 years instead of 5. Lots of lawsuits are pending because of DexCool causing problems in engines, just like mine and worse.

At least it wasn't a head gasket...

 

I wonder if the caps have been pressure tested on those bad rads?
anyone?

 

a radiator replacement was about $900 back in 2011 when I had a leaking radiator. I went aftermarket and put it in myself, figured it might only last 3-4 years also. There is a guy on one of the Hummer forums that put in an aluminum radiator from an old chevy for cheap if I remember right and of course there is the Ron Hall radiator ($$$).

 

It was around Marcg 2011 when I had my radiator problem too. I had the factory radiator rebuilt with new caps and trans cooler. Cost me around $300 I think. Of course, the trans cooler rupture two years later cost me $3500 for a new trans, and now this. I don't know if it can be blamed on the radiator rebuild or not. But I sure find the radiator in the center of a lot of my problems.

I might check for Chevy aluminum radiators with similar dimensions. Thanks!

 

Google- UGH-Another-Radiator-Bites-the-Dust hummer forum to find RCode's thread on his aluminum radiator.

 

Nice job on the aluminum radiator. Wish he had shown how he mounted it a little better. But I'm sure there are a lot of ways to mount it.

 

He posted about it in his build thread as well, I don't think he did a detailed write up on though. It does look nice and solves a couple of problems like the tranny cooler too.