2005 H2 here... Haven't had a single issue yet since I bought it new... *knock on wood* :D

When driving at around 70, I tend to hear a rattling inside, near the passenger side dashboard area and the driver side dashboard area. Tried a few things, but still haven't fixed the problem.

Oh man and you just got it, too. Good luck finding the issue! I washed and waxed mine yesterday for the first time in the garage. It took forever masking everything with tape to not get wax on black plastic pieces, the bitch looks awesome!!!

Yeah, definitely sucks...u have any pics u can post of your H2?

The rattle you are hearing is caused by the black plastic trim on the outside edges of your windshield. Remove them and run a bead of RTV silicone close to where the edge of the plastic meets the windshield and put them back on. Wait a couple hours for it to set up and take it for a spin. This was a VERY common problem and most of the trucks got fixed at the dealer under warranty.

1. Windshield wiper circuit board
2. Cab lights always pop-up and cause a hissing noise at speed
3. Rusted side steps
4. Mirrors as described earlier

Overall VERY happy owner of a 2004 model with about 50k miles.

I use that Ice polish too, you can even wax the headlights, it's awesome!

Common Probs
 

'04, Speedo gauge replacement, climate control actuator replacement (the hard one on top), when it rains the wipers sometimes come on themselves and the seat heat on the drivers' side cycles until things dry out. Guessing moisture gets in the wiring somewhere. Amazing what you can get used to.

I have owned my 05 H2 for about 4 years.(50000 miles) Overall its been great. My Problem areas have been

Windshield wiper circuit board short from moisture replaced (common problem)
Tach isn't reading Correctly replacing Cluster
Door Lock Switch Short