5th Gear Kit | Nissan FS5W71 (2WD)
Description
Helical 5th-gear pair for Nissan FS5W71 2WD manual transmissions. The set includes the mating mainshaft and countershaft gears (21/39 teeth) designed to interface with the OE synchronizer for quiet operation and high load capacity. Manufactured from case-carburized alloy steel and precision ground, these gears deliver excellent wear resistance, tooth strength, and consistent engagement—ideal for rebuilds or quality replacement.
Specification
Tooth Count: 21T / 39T
Gear Form: Helical
Material: SCM415 / SAE 8620 carburizing alloy steel (or equivalent)
Heat Treatment: Carburized & quenched, tempered
Surface Hardness: HRC 58–62 (tooth flanks), tough core
Manufacturing: CNC turning & hobbing; corrected dog teeth & deburring; ground bore and faces
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Model:NIS-5C(A-201)