Also, how much size difference is there now between the diameter of the left front drum versus the right front drum. Center plane brakes are unusually sensitive to variations in diameter. Wayne In addition to what has been posted by others, brake shoes must fit the drum. New shoes with a proper arc will have about .020" clearance at the ends when seated in the drum (drum and brake shoe off car). If the ends hit first, a very erratic brake action will result. Proper tools cam grind shoes to fit the drum. Tooling to accomplish such is far obsolete; operator health concerns, mostly. Practice of arcing shoes was a necessary operation when drum size was above a reasonable limit. That limit is not set at (generally) .060" above nominal and relined shoes are factory cam ground to accomodate this number. Something we see in high mileage drum brake cars and trucks is wear at the support pads where the shoes rest against the backing plate (brakes noisey and grab and don't release smoothly). These pads must be super smooth and in a plane. Welding and grinding will restore the surfaces. Light coat of synthetic brake grease (I still use NeverSeez) on the pads lets the shoes move smoothly. I live in a DRY area. Even so, the slightest bit of moisture in the air and after an extended park period, I will have a first application brake noise situation with, in particular, one of my cars. HTH Warren Anderson Sedona,AZ