im not nearly running that distance, but i have worked my way from being able to barely run 1 mile to closing in on 10. I try and keep my running to every other day at the most, usually only 3 times a week, as im focusing on cardio alot right now, heres some things that have helped me get up to distance and i havent had any knee pain/hip or whatnot and im actually a pretty injured guy and weigh 230 or so so im not light by any means.
Get a few pairs of shoes, i like one pair to wear during the day just at work w/e, then i like two pairs for every other day exercise, switching between the two really keeps the cushion decompressed and gives full support. This shit helps!
Fish oil, MSN, Glucosamine, these supplements have really helped all my joints, there the only thing i take.
Roll the fuck outta ur it bands, hams, glutes, and hips, stay mobile.
Do gym exercises that reinforce knee/hip/glute stabilization like split squats, reverse lunges in addition to the normal squats and deads.
DOnt try to run max distance every time, switch between speed days with moderate distance, long days and even just light moderate recovery days, you dont need to kill it every time to see slow steady progression.
Try to run on trails/non pavement, for the less impact. Also i find trails are alot harder so when i go for a pavement distance run after doing trails alot it always feels alot easier and faster.
hope some of that is applicable