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Drive Pinion and Ring Gear Identification

Drive Pinion and Ring Gear Identification
Production drive pinion and ring gears are manufactured by using a 2-cut or a 5-cut method. The gear tooth contact patterns that are produced from each style of gear set differ slightly. A 2-cut gear will produce a pattern that is bias from the toe to the heel of the tooth (drive side), while a 5-cut gear set will produce a square pattern from the toe to the heel of the tooth (drive side). When diagnosing the gear tooth contact pattern, regardless of what type of gear set it is, a correct pattern will be centered within the area of the tooth, from toe to heel and from top to bottom.

Gear Tooth Nomenclature





The side of the ring gear tooth which curves outward, to is convex. is the drive side (4). The concave side is the coast side (3). The end of the tooth nearest the center of the ring gear is the toe end (2), The end of the tooth farthest away from the center is the heel end (1)