Checking in with my 03 V8 4wd. 301k miles.
It was a one owner vehicle to 270k and I got it from the second owner at 300k. I haven't checked with the local dealer to get all of the service records. It had a timing belt at 270k. So far I've done:
Valve cover gaskets. Pretty sure they were original, they had shrank so much the valve cover bolts could be loosened by hand.
Lower radiator hose was swollen and leaked at the radiator outlet.
Replaced All fluids because unknown mileage on them. Front diff drain plug was seized.
One broken wheel stud on rear
The CV boots are dry and cracking but have not busted yet, unsure if original, I'd imagine they were replaced at some point.
Has the dreaded transfer case actuator leak but it's not terrible, just a drip every couple days. currently trying the blue devil stop leak, will probably just live with it until I have time to fix it properly.
AC works great all original
transmission shifts better than my 2013 Tahoe. All original. Low range and DAC work fine.
Getting 17-18mpg with a mix of 80mph highway/city driving.