4.57  Ratio M/W-Gleason 12” Gears are produced from 9310 alloy. These Ring and Pinions are the next step in durable gearing. The M/W Gleason series gears have a ground tooth form and are Cold Stabilized, Shot Peened and REM isotropic surface finished. These gears fit MW modulars with series 2 spool (P/N  53104) . Pinion shaft has a 3/8" hex for oil pump drive. These Gears are the latest improvement for the 12” Modular Rears.