I realize my truck has a few miles 85,000 or so & I puchased it used, (I am die heart GM guy)... my last truck had the same drive train (02 Denali) - never had a single issue with that truck with roughly the same miliage as my H2. My H2 was previously owned by a female & may have been lack of maitenance for some of the items (no offense to any woman members) , anyways cosmetically the truck is mint, but here is the list of things that I have fixed or I am in the process of fixing, feel free to add your expirences & or problems.
Keep in mind I just got my h2 in Dec 2008....

Header bolts busted (upgraded to headers-no big deal just a pita)
Climate control module burnt out ($130)
Front wheel bearing ($250)
Air ride (has issues) - likely need new air bags (slow Leak)
Thermostate - threw a code - -replaced
door seal leaks.. that was fun chasing leaks for a week
air bag light stays on
cluster went wacko one day - lit up like a xmas tree

thats all I can think of right now
also have a list of recalls done on the truck 2 pages long

whats next?

 

What's next is the trans cooler taking out the tranny like mine did. A new radiator or an external trans cooler would be on my list if I were you.

 

looking forward to that.... Is that a common problem as well?? on 6.0L GM's

 

On my 2003 H2 I put 48,000 miles on it from new. Only problem was a bad water pump replaced under warranty.

 

You have to remember our trucks (i have a 03) is 6 years old. I have a few issues, the one getting my goat is this dam knock sound when i hit the gas. I was thinking it was the gas, but i put high test and still have it ... its ok when idle but when you hit the gas you can hear it ... its not the valves, or atleast i dont think so. My truck gets oil chnages every 3000 miles.

 

Part of the game it seems. Iv had mine 5 months, so far its had new waterpump, pulleys, belts.

Developed a misfire, new plugs, leads and now coils.

Exhaust rotten and CAT has collapsed totally.

Air Suspension developed a leak, when it wants to. Othertimes its ok.

All good though. One day it will just work, and not need anything tending to. One day lol

 

Ok I don't feel alone here...

 

my air suspension problem is also intermittant, seems to have a mind of it's own

 

I feel very fortunate having read all these problems, and having none of them so far. <looks for something wooden to knock on>

I have 110k on my 2004 and the only issue I had was a couple times my speedo went on the fritz and offset itself by 22 mph...

I think i'll do some inspecting of the previously mentioned items.

 

I've put it down to a leak or new airbags needed. Best bet, is get a sqirty bottle, spray all the lines/bags and turn it on..if and when it leaks it'l bubble like mad helping you find it. Slightly harder when its intermittent.

If its airbags..They're on Ebay and they're cheap. Around $120 i think each. Not bad given what they are.

Im personally considering converting it to conventional suspension. Sick of Air bags and they can be unreliable. The extra bit of ground cleanrance on a push of a button can be useful sometimes.

$300 buys you a kit to convert the suspension to conventional springs, im on the edge of ordering. Problem free afterwards. I can then remove the air compressor and use the space to fit an LPG tank up out the way