My 2008 H3 Hummer has ended up costing me a ton of money! The radiator cracked recently and it was like a domino effect of other issues to follow. Like I said, the radiator cracked as I was driving down the freeway...smoke started blowing out of the hood as it started to overheat so I was desperately trying to find a place to pull off of a busy freeway. I had to end up pulling onto the shoulder that wasn't wide enough so it was still parked partially on the busy freeway. I had no other choice because at this point it was smoking like a train and it was obstructing my view so I was afraid it was on fire. After I pulled over & put my flashers on, cars were speeding past me honking because I was partially in the freeway. Luckily, I didn't get hit by another car but it was certainly a close call. To make matters worse, I had it towed to a my mechanic which was over 200 miles away (I highly recommend AAA membership). He informed me that the radiator was cracked which caused coolant to leak into my transmission, ruining my transmission! The Mechanic explained that when the coolant leaks into the transmission the transmission is doomed. He explained that the coolant eats away the adhesive on the internal clutches, torque converter, etc... I walked away with a $3800.00 bill. My Mechanic told me that this is a common problem with the H3 Hummers, he has seen this same problem with 4 others!