20CrMnTi Induction Hardened Shift Fork Shaft for Manual Transmission Gearboxes

Product Specification

20CrMnTi Induction Hardened Shift Fork Shaft for Manual Transmission Gearboxes

The automobile shift fork shaft is a core precision transmission part of manual gearboxes, mainly used to control shift forks for gear shifting, including 1st/2nd‑gear fork shaft, 3rd/4th‑gear fork shaft, reverse‑gear fork shaft and self‑locking fork shaft. Manufactured from high‑quality alloy structural steel such as 45# steel, 40Cr and 20CrMnTi, processed by precision turning, milling, induction hardening and grinding, it features high strength, high hardness, wear and impact resistance, high dimensional accuracy, low deformation and precise self‑locking. Matched with shift forks, synchronizers, positioning pins and springs, it realizes smooth shifting, gear self‑locking, anti‑gear jumping and anti‑gear disengagement. Widely used in manual gearboxes of passenger vehicles, commercial vehicles and construction machinery, it is a critical component ensuring shifting performance and driving safety.

Product Features

• High hardness & wear resistance: Induction‑hardened positioning grooves and sliding surfaces with HRC52‑60 hardness, resisting wear and jamming under long‑term reciprocating motion.
• Precise self‑locking structure: High‑precision self‑locking and interlocking grooves deliver clear gears and prevent gear jumping or disengagement.
• High dimensional accuracy: Strict control of shaft diameter, groove spacing, parallelism and concentricity ensures accurate shift stroke and no looseness.
• Impact & fatigue resistance: Overall quenching‑tempering provides good toughness against frequent shifting impact without fracture or deformation.
• Smooth low‑friction surface: Precision‑ground journals with anti‑rust treatment reduce sliding resistance for smooth, light shifting feel.
• Standardized universal structure: Compatible with mainstream MT gearboxes with strong interchangeability for easy maintenance replacement.
• Corrosion & high‑temperature resistance: Stable under transmission oil and high‑temperature conditions, resisting rust and deformation.
• Complete specifications: Fits gearboxes for mini‑cars, passenger cars, trucks, agricultural machinery and construction machinery.

Technical Parameter Table

Main Applications

• Shift control fork shafts for 1‑2, 3‑4, 5th and reverse gears of manual gearboxes.
• Core parts of self‑locking and interlocking mechanisms for gear locking and mis‑shift prevention.
• Shifting systems of MT gearboxes for passenger vehicles (sedans, SUVs).
• Transmission components for commercial vehicles: trucks, buses and vans.
• Manual gearboxes for construction machinery, agricultural machines, forklifts and tricycles.
• Replacement and OEM parts for gearbox maintenance.
• Manual shifting mechanisms for low‑speed new‑energy vehicles and special vehicles.

 Product Advantages

• Stable gears without jumping: High‑precision self‑locking grooves ensure tight ball fit to avoid disengagement.
• Smooth shifting feel: Precision‑ground shaft surface reduces friction for light, jamming‑free shifting.
• Long wear‑resistant life: Hardened surface resists transmission oil corrosion, extending service life by 2–3 times.
• High strength & fracture resistance: Alloy steel + overall tempering prevents bending or breaking under heavy load and impact.
• High precision without deviation: Strict control of concentricity and parallelism ensures accurate shift stroke.
• Strong versatility: Compatible with over 95% of MT gearboxes for easy replacement.
• Cost‑effective: Graded material options meet performance‑cost requirements for various vehicles.
• OEM quality: Identical dimensions, hardness and groove positions to OEM parts for direct replacement.

Production Process

• Raw material inspection: Flaw detection, hardness and composition test for 45#/40Cr/20CrMnTi.
• Cutting: Fixed‑length steel cutting and deburring.
• Rough turning: CNC rough turning of outer circle, steps and end faces.
• Groove milling: Milling of self‑locking, interlocking and fork clamping grooves.
• Overall quenching‑tempering: Tempering to HRC28‑35 for improved toughness.
• Induction hardening: Local hardening of sliding surfaces and grooves to HRC52‑60.
• Precision grinding: OD grinding to meet concentricity and roughness standards.
• Chamfering & deburring: End chamfering to prevent assembly scratches.
• Surface treatment: Blackening/phosphating + anti‑rust oil for corrosion resistance.
• Full inspection & warehousing: Comprehensive check of dimensions, hardness, groove precision and straightness before packaging.

Why Choose us?

• 7-axis CNC Grinding: We adopt high-precision 7-axis CNC grinding machines, holding tolerances as tight as ±5μm, ensuring gears run quietly, smoothly and with outstanding durability.
• Strong technical expertise: Our core R&D team includes doctoral and master’s professionals specializing in spiral bevel gear technology, providing strong technical support for complex projects.
• Rigorous testing & high precision: All gears undergo 100% inspection with Gleason metrology systems. We can achieve DIN 6 grade accuracy with strict control over tooth profile and direction errors, keeping our quality at the industry-leading level.
• High transmission efficiency: Our gear designs support a single-stage reduction ratio of up to 300:1, with actual transmission efficiency reaching over 95%, greatly improving energy utilization.
• Excellent durability & cost efficiency: Our gears deliver 40% lower lifecycle cost and a failure rate below 0.5%, ensuring stable long-term operation and reduced maintenance costs.
• Fast response & short lead time: Supported by our digitalized production process, we are able to shorten the delivery cycle to only 20 working days, helping you accelerate project development and launch.
• Professional custom design capability: We provide fully customized gear solutions for applications requiring high-reduction, high-speed, heavy-load, low-noise, and special small-tooth profiles, based on your actual working conditions.