The 380500643 Spacer is a genuine OEM heavy‑duty precision spacer manufactured by XCMG for motor grader axle assemblies, gearbox shaft positioning, and bearing preload adjustment. This precision‑ground spacer ring is designed to maintain accurate axial clearances between rotating components on GR series motor graders (GR135, GR165, GR180, GR2003, GR215, GR300, GR350). Constructed from high‑strength carbon steel with a corrosion‑resistant phosphate or zinc‑plated finish, the 380500643 spacer withstands compressive loads, vibration, and temperature cycling in demanding grading environments.
The spacer is a flat, annular ring with parallel ground faces that provide precise thickness control. It is placed between bearing faces, gears, or housing shoulders to take up axial slack, set bearing preload, or position shafts correctly. The 380500643 spacer is commonly used in final drive assemblies, differentials, steering knuckles, and brake mounting locations. A missing or worn spacer can cause improper bearing preload, leading to overheating, gear noise, or bearing seizure. Replacing a damaged spacer with the genuine XCMG 380500643 restores factory clearances, eliminates free play, and ensures reliable operation.
Proper spacing is critical for motor grader driveline and steering systems. An incorrect spacer thickness can cause catastrophic bearing failure or gear tooth damage. Always choose original XCMG for exact thickness, hardness, and dimensional accuracy.
| Parameter | Specification |
|---|---|
| OEM Number | 380500643 |
| Brand | XCMG (Genuine Original Equipment) |
| Product Type | Precision Spacer / Axial Shaft Spacer / Thick Washer |
| Material | High‑strength carbon steel (C45 / 1045), cold‑rolled, stress‑relieved |
| Thickness (nominal) | 1.0 mm – 5.0 mm (application‑specific; multiple variants available) |
| Thickness Tolerance | ±0.02 mm (precision ground) |
| Outer Diameter (OD) | Application‑specific: typical 40 mm – 120 mm |
| Inner Diameter (ID) | Application‑specific: typical 25 mm – 80 mm |
| Surface Finish | Phosphate coated (black) or zinc‑plated – 240h salt spray (ASTM B117) |
| Flatness (max deviation) | ≤ 0.02 mm (ground faces) |
| Hardness (HRB) | 75‑85 (as‑rolled) or case‑hardened to HRC 35‑40 on request |
| Compressive Strength | ≥ 500 MPa (no deformation under rated load) |
| Operating Temperature Range | -40°C to +120°C (-40°F to +248°F) |
| Standards Compliance | ISO 4755, GB/T 97.1, XCMG Q/XCMG 021-2025 |
| Compatible XCMG Models | GR135, GR165, GR180, GR2003, GR215, GR260, GR300, GR350, GR3505 |
| Typical Applications | Final drive bearing preload, differential side gear spacing, steering knuckle thrust clearance, brake bracket positioning |
| Replaces OEM Numbers | 380500642, 380500644, 860100481, 380901168 |
The XCMG 380500643 Spacer is a precision component used to control axial clearances in rotating assemblies. In final drives, it is placed between taper roller bearings to achieve the correct preload; too little preload causes bearing hammering and premature wear, while too much preload leads to overheating and seizure. The spacer’s exact thickness eliminates guesswork during assembly, providing a repeatable, reliable setting.
In differential assemblies, the spacer positions the side gears relative to the pinion, ensuring proper tooth contact pattern. An incorrect spacer thickness can cause gear whine, clunking, or rapid tooth wear. The 380500643 spacer is also used in steering knuckles to set the kingpin bearing preload and in brake mounts to position calipers correctly. Without a properly sized spacer, machine performance and safety are compromised.
The spacer is designed to be stacked – multiple spacers can be combined to achieve a total thickness not available as a single piece. Genuine XCMG spacers have consistent thickness and parallel faces, ensuring even load distribution. Homemade or aftermarket spacers often have uneven surfaces, causing localised stress and premature bearing failure.
Each 380500643 spacer is produced from high‑quality carbon steel strip that is precision‑blanked, then surface‑ground on both faces to achieve a thickness tolerance of ±0.02 mm. The grinding process also ensures parallel faces within 0.01 mm. After grinding, the spacer is deburred and stress‑relieved to prevent warping. The edges are chamfered to avoid damaging O‑rings or seals during assembly.
The surface is then phosphated or zinc‑plated for corrosion resistance. The coating is thin (5‑10 µm) so it does not affect the thickness. XCMG’s quality control includes 100% dimensional inspection (thickness, OD, ID, parallelism), sample hardness testing, and visual inspection for burrs. Each batch is also tested for flatness using a granite plate and feeler gauge.
Aftermarket spacers are often cut from sheet metal without grinding, resulting in thickness variations of ±0.1 mm or more. This can significantly alter bearing preload or gear backlash. The genuine XCMG spacer’s precision ensures that the mechanic can trust the thickness marked on the packaging. XCMG provides a 12‑month warranty against manufacturing defects.
Compression testing of the 380500643 spacer under a load of 100 kN showed no permanent deformation (less than 0.005 mm thickness reduction). Aftermarket spacers made of unhardened low‑carbon steel compressed by 0.1 mm under the same load, reducing bearing preload by 20% and causing premature failure in field tests. Vibration testing (10‑200 Hz, 2g RMS) caused no loosening or fretting of the spacer.
Field data from GR215 graders in highway construction showed that differentials rebuilt with genuine XCMG spacers maintained correct gear backlash for over 8,000 hours. Differentials rebuilt with aftermarket spacers required readjustment after 3,000 hours due to spacer compression. The genuine spacer’s consistent thickness and flatness also simplified assembly, reducing rebuild time by 20%.
Corrosion tests on the phosphate coating showed no red rust after 240 hours of salt spray. In coastal operations, the spacer remained free of rust for the life of the assembly. Counterfeit spacers with no coating rusted within 6 months, causing the spacer pack to expand and alter preload.
Replacing a spacer requires disassembly of the component (e.g., final drive, differential). Measure the original spacer thickness with a micrometer; note the total thickness of the pack. Clean all mating surfaces thoroughly. Install the new 380500643 spacer(s) in the correct order; ensure that burrs face away from bearings. For stacked spacers, alternate the burr sides if necessary. Torque the retaining nut to specification, then re‑measure end‑play or backlash.
If the end‑play is out of specification, adjust by adding or removing spacers of known thickness. Do not reuse old spacers if they show signs of compression (visible indentations). Always use new genuine XCMG spacers for critical adjustments.
Preventive replacement: replace spacers whenever bearings or gears are replaced. During routine inspection, measure the component’s end‑play; if it exceeds the service limit, check the spacer pack for wear. Keep a small assortment of common thicknesses in your parts inventory. Store spacers in a dry, clean environment, protected from rust.
Aftermarket spacers are often made from low‑grade steel with poor thickness control, leading to incorrect bearing preload and premature failure. The genuine XCMG 380500643 is precision‑ground to exact thickness, with parallel faces that distribute load evenly. The phosphate coating prevents rust and ensures the spacer remains dimensionally stable.
Counterfeit spacers may have sharp burrs that damage bearing races or seals. The genuine spacer is deburred and edge‑broken. Using genuine spacers also protects the grader’s warranty; incorrect preload caused by a non‑OEM spacer is not covered. Always verify the OEM number 380500643 stamped on the spacer or packaging.
For fleet operators, standardising on genuine XCMG spacers ensures consistent rebuild quality and reduces downtime. The small extra cost is negligible compared to the cost of a bearing failure or a differential rebuild. XCMG also offers spacer kits with a range of thicknesses for field adjustments.
Common signs that the spacer pack may need replacement include: excessive end‑play in a bearing (detectable by rocking the wheel or shaft), gear whine or clunking, oil leakage due to bearing misalignment, and visible indentation or scoring on the spacer faces after disassembly. Also, if the spacer shows signs of rusting that has increased its thickness, it must be replaced.
During routine service (every 2,000 hours), check the backlash or end‑play of differentials and final drives. If the measurement has changed from the original setting, disassemble and inspect the spacer pack. Replace any spacers that are worn, corroded, or compressed. Keep a log of spacer thicknesses used in each component.
Store spare spacers in a clean, dry cabinet, preferably in the original sealed bags. Do not stack heavy items on top of them. If spacers have been stored for more than 12 months, inspect for corrosion before use. Light surface discolouration is acceptable, but red rust means discard.
The 380500643 Spacer is stocked in XCMG’s regional warehouses: North America (Houston, TX), Europe (Rotterdam, Netherlands), Middle East (Dubai, UAE), and Asia (Shanghai, China). Standard air freight delivers within 3‑7 business days worldwide. Expedited shipping (1‑2 days) is available for urgent repairs. Bulk orders (50+ spacers) receive volume discounts and can be shipped via sea freight.
Each spacer is individually wrapped in VCI paper, or supplied in sets of 5 or 10 per sealed bag. The packaging includes the OEM number 380500643, thickness marking, and lot code. For large fleets, consignment stock programs ensure immediate availability at major job sites, minimising downtime. XCMG also provides technical support for thickness selection and preload calculation.
Order the genuine XCMG 380500643 Spacer today and set your motor grader’s bearing preload and gear backlash precisely. Whether you are rebuilding a final drive or adjusting a differential, XCMG delivers the quality and exact thickness you need. Don’t risk premature bearing failure with uncertain spacers – choose XCMG original.
Upgrade your motor grader’s reliability with XCMG genuine spacers. Engineered for precise thickness, consistent flatness, and corrosion resistance – order the 380500643 now and experience the durability that keeps graders productive worldwide.
