i think thats going a bit techinical for the poor fellow isnt it? :) for the lay person, have a tyre pressure checker from your local super crap or repcrap or autocrap for like 10 bucks. check your tyre pressures everytime u fill up the car. for the 2011 corolla, i recommend 35 psi not the factory recommendation of 32psi. no u will not pop the tyre at this pressure. as said above, tyres that have toe in wear the outer part of the tyre (i think correct if wrong) and tow out wears the inner. from factory, all cars have slight toe in for highway stability and safety in the straight line. u've travelled a fair bit, i'd say its fair that your tyres should be replaced soon. weight has nothing to do with the tyre wear. unless u weigh 200 kgs -_-