I've got about 215k on my 2005 Yukon. Bought it about 10 months ago with 205k on it. I had them replace the steering box (it was leaking) and the alternator (was whining) before I would buy it. A few months ago I had to replace the TCM... there was a remanufactured part on there... replaced it with a Dorman. The truck is very solid, runs like a dream. I bought it for distance driving and we've made two trips to Vegas with it so far (seeing the grandson, not gambling) and two to Idaho.
I'm sure there will be some repairs coming up in the next couple of years, but if I get three years out of it I'll be happy. I only paid $5k for it (plus $1k for new tires).
Right there with you, except I only paid $3500 for mine and everything is in really good shape. The biggest thing I’m trying to fix is it doesn’t like taking fuel. Already replaced the charcoal canister and the small filter off of that. I’ll get it straight when I get some down time or either just take it to the mechanic who does all of our patrol cars.