Mine is in the 160k range I bought from a used dealer gave 30days warranty took 3 times for oil leak they screwed off & wiped it clean telling a story each time checking they hadn't done anything. I did get them to replace drivers seat because adjust motors were bad. Should have fought in court the oil leak issue as by time I diagnosed the rear main seal they argued past their warranty & they would half cost of repairs at some side mechanic shop? I never thought to make them give receipts proving I returned 3 times for oil leak inside their warranty period.
Anyway I did rear main seal myself, as driving went many smaller issues found, the break sensor was faulty(cruise control wouldn't activate). I chased idle issues & abs stabilitrak lights intermittent.
Replaced battery, gas pedal, throttle body, and many other things.
Found the biggest problem causes were, grounds to frame all needed cleaning & tightening, the driver side valve cover needed upgrade oil pcv hole, added oil catch cans both sides pcv valve cover lines, my ac-delco spark plugs melted? Idk how but that wasn't fun figuring out thought of burning the truck until figured it out... recently replaced fuel pump, & as many sensors as possible to be sure computer system gets correct readings. Have intake manifold off today after seeing you tube video shows vlom? (Active Fuel Management solenoid plate) bolts were not torqued well enough? Factory? 11 total 13mm bolts there were 8 on mine I could remove with fingers only 4 were seated holding it.
I'm sure that was leaking oil slowly aswell, hopefully I saved mine from the lifters collapse/valve problems.
Torqued them back down & finishing seals as put back together. New fuel injectors since have manifold off.
I do have to replace dust covers on 4x4 axles leaking oil/grease starting to crack, replaced steering shaft dust cover recently.
Even with the many small issues I've had to figure out & fix its never broken down always made it back to try another part.
Utility of truck with space & storage I love carry tools, & gear to be prepared for almost anything
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Room for my family & easily tows our trailer. I enjoy figuring out the workings of the truck, I'm also able to clean and degrease parts mechanics never do. I hope to upgrade & keep this truck as long as possible.