24-04-2018, 08:15 PM
quite common, fords used it on the escort/orions back in 84 onwards. as you have discovered, the leading shoe gets dragged into contact with rotating drum (called self-servo effect) and does most of the work. The trailing shoe doesnt wear as much as the drum surfac is effectively sliding over its leading edge...stopping it from "digging in" and also not wearing it out. in reverse gear the roles are reversed and trailing shoe now becomes leading shoe and it does "dig in" and do the work.