I have a 2000 chevy silverado z71 4x4 with 190,000 and my 3rd tranmission. Am i gonna hit 300,000? With normal maintence. I run Royal Purple every oil change. I'm 19 so im kinda hard on it at times. Having 4x4 dont help me out with taking care of it. That button is So tempting at times haha. I have the 4l60e tranmission. I'm 19 but im a Master ase tech. So i do my own work, when this motor goes ill be replacing it. Ill put pics on here soon. i just got a tatto on my back of the truck all detailed suspension exhaust even the z71 is on there. My dad is the orginal owner he he never really use 4wd much. and he droves like a normal person most of the time. but he pulled a bobcat quite a bit with it. Anyways my new tranmission is bulletproof. 3500 dollars later/. i have a mild shift **** and and tranny cooler after it runs through the raditor. I love this truck i hope to keep it around fora long time. its in good shape. I've always had fords and now that i have a chevy i will never go back to a ford. i think the 5.3l last so long is because you really dont have to run any rpms to run down the road..