The 805639609 Pin 5×50 is a genuine OEM cylindrical dowel pin manufactured by XCMG for motor graders and heavy construction equipment. This precision‑ground pin, also known as a solid locating pin or hinge pin, provides an accurately sized, high‑strength pivot for linkages, cylinder mounts, and frame connections on XCMG GR series motor graders. Manufactured from case‑hardened alloy steel with a precision surface finish and corrosion‑resistant zinc‑plated coating, the 805639609 pin is designed to withstand extreme shear and impact loads in demanding grading environments.
The Pin 5×50 dimensions – 5 mm diameter and 50 mm overall length – are standard for many small pivot joints on XCMG GR135, GR165, GR180, GR215, GR260, GR300, and GR350 motor graders. This pin directly replaces worn, bent, or corroded pins on blade lift linkage clevises, circle drive yoke pins, articulation joint stops, and steering cylinder attachments. The pin features a chamfered lead‑in on both ends for easy insertion and a precision ground surface (Ra ≤ 0.8 μm) to minimize bearing wear.
A worn or bent pin 805639609 causes excessive radial play, leading to accelerated bushing wear, noisy operation, and misalignment of critical assemblies. Replacing a damaged pin with the genuine XCMG 805639609 restores original clearances, eliminates play, and protects the more expensive mating components.
| Parameter | Specification |
|---|---|
| OEM Number | 805639609 |
| Brand | XCMG (Genuine Original Equipment) |
| Product Type | Cylindrical Dowel Pin / Solid Pivot Pin |
| Diameter | 5.00 mm (f7 tolerance: -0.010 / -0.022 mm) |
| Overall Length | 50.00 mm ±0.3 mm |
| Material | Case‑hardened alloy steel (20CrMnTi / equivalent) |
| Surface Hardness | 58 – 62 HRC (case depth 0.5 – 0.8 mm) |
| Core Hardness | 35 – 45 HRC |
| Surface Finish | Centerless ground, Ra ≤ 0.8 μm |
| Chamfer | 1.0 mm × 45° (both ends) |
| Corrosion Protection | Zinc plating (8‑12 μm) + clear chromate |
| Shear Strength | ≥ 450 MPa (tested per ISO 8748) |
| Salt Spray Resistance | ≥ 240 hours (ASTM B117) without red rust |
| Operating Temperature Range | -40°C to +120°C |
| Standards | ISO 8734 (Dowel pins), ISO 9001:2024 |
| Compatible Models | XCMG GR135, GR165, GR180, GR2003, GR215, GR260, GR300, GR350 |
| Superseded Part Numbers | 805639600, 805639605 |
The XCMG Pin 5×50 (805639609) is a small but crucial component in the grader’s articulation and control systems. It acts as the primary pivot for rod ends, clevises, and hydraulic cylinder attachments. In the blade lift linkage, this pin connects the lift cylinder rod end to the lift arm bracket. Any wear or bending here allows blade drift and reduced grading accuracy.
On the circle drive assembly, the pin 805639609 secures the yokes that rotate the moldboard. A tight pin fit ensures that the circle rotates smoothly without backlash, preserving the drive gear alignment and preventing premature wear of the circle drive motor.
The pin also appears in steering linkages, wheel lean mechanisms, and articulation joint stops. With a diameter of 5 mm, it is often used in lighter‑duty pivots where larger pins would be over‑specified. Its high case hardness resists indentation from bushing wear, while the tough core absorbs shock loads without bending.
Each 805639609 pin is manufactured from premium 20CrMnTi alloy steel. The blank is centerless‑ground to a pre‑hardened dimension, then carbonitrided in a controlled atmosphere furnace to achieve a uniform case depth of 0.5‑0.8 mm and surface hardness of 58‑62 HRC. The core remains ductile (35‑45 HRC) to resist brittle fracture.
After heat treatment, the pin is finish‑ground on a centerless grinder to achieve the f7 tolerance (5.000 -0.010 / -0.022 mm). The surface finish is carefully controlled to Ra ≤ 0.8 μm, providing an optimal running surface for sintered bronze or plastic bushings. The chamfers are then cut, and the pin is zinc‑plated with a clear chromate top coat.
XCMG’s quality control includes 100% dimensional inspection of diameter, length, and chamfer angle using laser micrometers. Random samples are hardness‑tested (sectioned from each batch) and subjected to a salt spray test (240 hours). Only pins that meet all criteria are accepted for packaging under the XCMG Genuine Parts label.
Replace a worn or bent pin 805639609 by first disconnecting the linkage or removing the retaining hardware (nut, cotter pin, or spring clip). Clean the bushing bore thoroughly and inspect for ovality or scoring. The pin should be a loose slip fit in the bushing – it should push in by hand with slight resistance.
If the bushing is worn, replace it before installing a new pin. The pin itself acts as the sacrificial wear component; a worn pin with reduced diameter will accelerate bushing wear. After inserting the new pin, secure it with the original retaining method. Lubricate with a light coating of grease to prevent corrosion and ease future disassembly.
Do not hammer the pin directly; use a brass drift to avoid damaging the chamfer. Never reuse a pin that has been removed – the press fit or retaining grooves may be compromised. Always install a new 805639609 pin when rebuilding any linkage.
Aftermarket pins are often made from low‑carbon steel that is not case‑hardened, or they use inconsistent heat treatment that leads to soft spots and rapid wear. The genuine XCMG pin has a controlled case‑hardening profile, ensuring consistent hardness across the entire surface. Aftermarket pins also frequently have poor dimensional accuracy, causing either a loose fit (play) or an interference fit (cannot be installed).
Counterfeit pins may have zinc plating that flakes off, exposing steel to rust. The 805639609 has a certified zinc‑chromate finish that passes 240‑hour salt spray testing. In addition, genuine pins are 100% inspected for surface finish; aftermarket pins are not. Using a genuine pin prevents premature loosening and protects your grader’s expensive bronze bushings and cast yokes.
XCMG provides a 12‑month warranty against manufacturing defects. Each pin is laser‑etched with the XCMG logo and part number. Choose genuine for reliability and safety.
Common signs that the pin 805639609 needs replacement: visible wear steps on the pin surface, reduced diameter (measured with a caliper) below 4.95 mm, rust pitting, bent pin (visible when rolling on a flat surface), and excessive radial play in the joint. Clicking or clunking during operation also indicates worn pins or bushings.
Preventive replacement is recommended every 4,000 operating hours or whenever the associated linkage is removed for service. The cost of a new pin is negligible compared to the cost of a worn bushing or damaged yoke. During routine lubrication, inspect all pivot pins for corrosion or visible wear.
Keep a stock of 805639609 pins in your parts inventory. A bent pin can cause sudden joint seizure or breakage. Replace immediately if a pin is found to be bent.
The 805639609 Pin 5×50 is stocked in XCMG regional warehouses in North America (Houston), Europe (Rotterdam), Middle East (Dubai), and Asia (Shanghai). Standard air freight delivers within 3‑7 business days worldwide. Expedited shipping (1‑2 days) is available for urgent repairs. Bulk orders (100+ pins) receive volume discounts and can be shipped via sea freight.
Each pin is individually wrapped in anti‑corrosion paper or supplied in sealed bags. For large fleets, consignment stock programs are available to ensure immediate availability and reduced downtime. Don’t let a worn pin compromise your grader’s joint integrity.
Order the genuine XCMG 805639609 Pin 5×50 today and restore precise pivot action to your motor grader’s linkages. This pin is a critical component for blade control, steering, and articulation. Keep spare pins in your service truck for every linkage overhaul, and always replace with genuine XCMG parts.
Upgrade your motor grader’s reliability with the XCMG genuine hinge pin. Engineered for strength, precision, and corrosion resistance – order now and experience the quality that keeps your grader safe and productive.
