2010 H3 Alpha/Offroad 55K. I noticed a small leak and took it to my local mechanic. He pressurized the system and coolant was squirting out drivers side top tank front. This will pay for about half of what the GMPP extended warranty cost me. I am glad I got it now. So it is off to my local Chevy dealer Monday morning. The dealer I have had do warranty work in the past is 2 hrs. away and I don't want to chance driving it that far. My local mechanic through his contacts sought out the best mechanic at the local Chevy dealer and I am going to request him. I know a radiator replacement is not rocket science but it always makes me nervous having a new mechanic working on my truck. Wish me luck.

 

That sucks, at least you have the extended warrany. When/if ours go I'm going to go the aluminum route like the guy on CHO.

 

Update: In at my local Chevy at 7:30 this morning and out at 10:00 with a new radiator. I was surprised they had one in stock. That radiator must not be exclusive to H3. GMPP Major Guard paid all but my $100.00 deductible. If it goes out again and I am out of warranty, I will look seriously at an all aluminum one. I thought I would report at least 1 good dealer experience.

 

The newer version of the GM radiator for the H3 has a slightly different shaped top tank to avoid contact with the radiator support, but on some rigs it still makes contact so to be safe I'd check yours to make sure there is proper clearance.
I was told by my dealership that the tank composite material was also supposed to be more robust than the earlier version to keep it from failing in what was the thin area of the tank. Not sure how accurate that statement is though.

 

The one that cracked on my 2010 I think did have a slightly different shape to the top than my 06 or 08 but it cracked anyway. The forward part of the top tank is tapered. I don't exactly remember what the 06 and the 08 looked like. Folks have blamed rubbing issues in the past and that could be true, but I think most of it is caused by thermo-cycling. I do a lot of starts and stops in my daily routine. The plastic just has so many heat and cool cycles in them before it starts to crack at the place there is less give which is near the crimp point.

 

I got a new dealer installed radiator back in 09 and it is plastic at the top with aluminum crimping along its entire top edge.
Do you have a picture of this "slightly different shaped tank", that you speak of ?
I am now curious as to which one I have
Thanks

 

I don't believe at all that mine cracked because of heating and cooling and a weak spot. The crack started exactly where it hit up against the frame of the rad support. The new one installed on mine is tapered and has good clearance at the spot it was hitting before, but I had to grind about 1/4" inch off the frame at the other end of the radiator because it then was hitting there. Was just a poor poor design all around, that people are still dealing with and GM tries to get out of fixing at all costs. Terrible in my opinion.

 

I think the important thing is to trim the metal where needed and,let the rad free float b4 attaching the center bracket and making sure it doesn't stress the rad position at all. somebody used that to push the rad away,not good!
cut the frame,let the rad float as free as possible.

 

As has been pointed out the in the main radiator thread, there are two problems with the factory setup. 1) the radiator support often made contact with the top tank and would either rub through the tank at that spot or put undue pressure on the tank which could possibly promote cracking. 2) the OEM upper radiator tank seemed to have a thin spot where it could crack over time with or without having the support contact problem.

No pictures of the new tank, but I believe there are some in the main thread. Tank is angled back to avoid contact, but some supports have such a large lip that they contact the tank anyway.

 

Can you guys help me clarify the following:

1. When I replace the radiator, how do I know I am getting the new model? Does it have a different item number?
2. Has anyone used the 'new improved' OEM radiator for around 60K miles to see that it does not crack again?
3. Are the cheap ($150-$200) substitutes good enough? Are there any modifications that have to be done in order to make them fit?
4. Is the working temp. realy supposed to go up when replacing to the 'new imporved' OEM radiator? I read it moved from the middle to around 2/3 of the gauge.

Thank you