So at a macro (how, if at all, should it change?) and microscopic level (what do the surfaces look like before and after) how does the break-in process compare on treated vs. standard gears? I'm a little confused by the 'ridges' reference. Aren't gears often run together during the manufacturing process to improve stress distribution, etc., and if so, how would the surfaces differ from those of low-mileage, properly broken-in 'used' gears?
