It has 170k on engine. Transmission was replaced 15k miles ago. He only put 22k miles on it in 10 years of ownership.
Things I’ve done:
-Multiple degreases and pressure washing engine bay and underneath.
-Valve cover gaskets
-All 4 O2 sensors (Denso brand)
-Exhaust gaskets and Felpro bolts. Had to use Dorman fix on driver side rear bolt was broke off flush. But now no ticks when cold or hot.
-Main and ac serpentine belt
-Upper and lower large radiator hoses
-Torsion bar bushings and new 2” lift torsion keys
-1.5" rear coil spring spacers
-kyb monomax shocks all around.
-Alignment
-Intermediate shaft and lower steering column bearing
-All 4 window regulators
-Fuel pump with sender. Installed Flex fuel pump since it had "robust fuel level sender". Had to change flat 4 plug to square 4 plug but it dropped right in my vin T which is LM7 5.3 non-flex.
-Front diff fluid (terrible dirty, prob original)
-Rear diff fluid (not bad was changed 10 years ago)
-Autotrac transfercase fluid (the special blue Fluid (looked good was changed 10yr ago)
-At home trans flush to maxlife synthetic atf. Disconnected trans cooler line at radiator and pumped fluid till new came out. Also dropped pan and new filter. Fluid looked pretty good, some grey clutch material in bottom of pan and on magnet but pretty minimal.
-power steering flush
-engine oil
-Carpet cleaning
-Steering wheel buttons (lights were out)
-rear hvac actuator. (was stuck on ac (blend door actuator)
-Driver heated seat bottom and back new heating elements
-spark plugs and wires. Plugs I pulled out had ngk and part # on one side but acdelco and part # on other side. Thought they were counterfeit but sent pics to ngk they said they were oem plugs, could be original at 170k
-Front Brake pads, Rear Brake pads, Parking Brake shoes.
-Greased all fittings
-sway bar links
-Z71 factory running boards
-Denali cluster with trans temp gauge
-Idler and pitman arms were replaced 20k miles and 8yr ago.
I've now put about 2k miles on it and it hasn't missed a beat. The blackbear tune made the biggest difference in seat of the pants feel. Also firmed up trans shifts. Towing my 3500lb enclosed trailer, it doesn't do as well as my 97 k1500 with 5.7 also blackbear tuned. Both are 3:73 gears. But the 5.3 does alright just has to downshift and rev sooner than the 5.7.