The post below on putting a hydraulic pump on a M and some answers brings up a question I would like to ask. Seems to be a lot of different answers as to when the increased strength camshaft gear 6760 DA started being used in farmalls. Does anyone know exactly when 6760 DA was first used in a production farmall. I think there should be a bulliten that IH sent out to dealers or parts depots anouncing the change of gears somewhere around if someone has some. I do have one anoucing the change to 6760 DB but haven't located one for change from 6760 D to 6760 DA. Any comments or help is welcome. From what information I have I think the change was made to the stronger gear from sometime in later 53 to later 54. Can't find proof that any M tractors came with gear 6760 DA.