Alright. my dad has a 1994 Toyota 2wd with a 22RE. its at about 115,000-120,000 miles, and in need of a timing chain. its clicking pretty badly between 2000-3000 Rpms. my friend and i told my dad that we would do it for him, since he doesnt have any extra time, fixing and running hay equipment and what not. ive been trying to get him to let us do it, but he wont do it yet. im afraid that its going to cause some major damage if we dont get it done fairly quickly, and i dont really feel up to doing some major work if this thing goes. i wanted to know A) about what is the MAX that you should let one of these timing chains go, as in milage, and B) other than major head damage, what else could happen?