what i failed to understand is how come ur 2009 corolla creating such problems? as u said i just sold my 05 cultus and never ran in any problem such as heatup or suspension. u just need to drive carefully..
abt brass/copper vs aluminium radiators, what i referred to is the quality of locally made brass radiators which are nothing but waste of money. plus as rightly said by xulfiqar, the mechanics have an itch to remove the thermostat valve which eventually lead to other problems where a significant decrease in engine's life is top of all.