The 800554251 Bearing is a genuine OEM heavy‑duty deep groove ball bearing manufactured by XCMG for motor grader fan drives, belt idler pulleys, gearbox shafts, and steering column supports. This high‑precision single‑row bearing is designed to accommodate radial loads and moderate axial loads with minimal friction, making it ideal for high‑speed rotating components on GR series motor graders (GR135, GR165, GR180, GR2003, GR215, GR300, GR350). Constructed from chrome steel (GCr15) with precision‑ground raceways and high‑grade steel balls, the 800554251 bearing delivers long service life, low noise, and excellent reliability in demanding grading environments.
The bearing features metal shields (ZZ) or rubber seals (2RS) on both sides to retain lubricant and exclude contaminants such as dust, sand, and moisture. The internal clearance is set to C3 (greater than normal) to accommodate thermal expansion in high‑speed applications. The bore diameter, outer diameter, and width follow ISO 15 standards, ensuring interchangeability and precise fitment. Typical applications include the fan drive idler pulley, alternator bracket, steering column shaft, and various pivot shafts where a standard deep groove bearing is specified. An incorrectly sized or poor‑quality bearing can cause overheating, noise, and premature component failure.
Replacing a worn or noisy bearing with the genuine XCMG 800554251 restores smooth rotation, eliminates play, and prevents secondary damage to housings or shafts. Aftermarket bearings often use inferior steel, have poor surface finish, or lack proper heat treatment, leading to rapid wear. Always choose original XCMG for exact dimensions, correct internal clearance, and proven material quality.
| Parameter | Specification |
|---|---|
| OEM Number | 800554251 |
| Brand | XCMG (Genuine Original Equipment) |
| Bearing Type | Deep groove ball bearing, single row |
| Bore Diameter (d) | 25 mm (typical – confirm per application) |
| Outside Diameter (D) | 52 mm |
| Width (B) | 15 mm |
| Basic Dynamic Load Rating (Cr) | 14.0 kN |
| Basic Static Load Rating (C0r) | 7.8 kN |
| Fatigue Limit Load (Pu) | 0.33 kN |
| Reference Speed (grease) | 14,000 rpm |
| Limiting Speed (grease) | 11,000 rpm |
| Internal Clearance | C3 (greater than normal) |
| Tolerance Class | P0 (ABEC‑1) standard, P6 on request |
| Material – Rings & Balls | Chrome steel GCr15 (AISI 52100), vacuum degassed |
| Hardness (HRC) | 60–65 |
| Cage Material | Pressed steel (J‑type) or polyamide (optional) |
| Seal / Shield Type | 2RS (double rubber contact seals) or ZZ (metal shields) |
| Grease Fill | Lithium‑based high‑speed grease (operating temp -30°C to +120°C) |
| Operating Temperature Range | -40°C to +120°C (-40°F to +248°F) |
| Standards Compliance | ISO 15, GB/T 276, DIN 625‑1 |
| Compatible XCMG Models | GR135, GR165, GR180, GR2003, GR215, GR260, GR300, GR350, GR3505 |
| Typical Applications | Fan idler pulley, belt tensioner, alternator support, steering column, gearbox shafts |
| Replaces OEM Numbers | 800554250, 800554252, 380901066, 860100466 |
The XCMG 800554251 Bearing is an essential component in many rotating systems on the motor grader. In the engine accessory drive, it supports the fan idler pulley, which maintains serpentine belt tension for cooling fan and alternator operation. A worn fan idler bearing can cause belt misalignment, overheating, and loss of charging – all leading to unplanned downtime. In the steering column, the bearing ensures smooth rotation of the steering shaft, providing consistent operator control. In gearboxes, it supports shafts that transfer power to the tandem drive.
The deep groove geometry of the 800554251 bearing provides high radial load capacity and low friction. The double rubber seals (2RS variant) retain the factory‑packed grease and keep out abrasive dust – a critical feature for graders operating in mining or desert environments. For higher speed applications, the ZZ (metal shield) variant offers lower drag while still providing splash protection. The C3 internal clearance accommodates thermal expansion when the bearing runs near its speed limit.
A failing bearing typically presents as a grinding noise, excessive vibration, or visible play when rocking the pulley or shaft. If left unattended, a seized fan idler bearing can cause the belt to burn through, potentially damaging the water pump and alternator. Replacing the bearing with the genuine 800554251 restores quiet operation, ensures reliable accessory drive function, and protects adjacent components. Always replace the bearing and the belt together for best results.
Each 800554251 bearing is manufactured from vacuum‑degassed GCr15 chrome steel, known for its uniform microstructure, high hardness, and excellent rolling contact fatigue resistance. The rings and balls are hardened to 60‑65 HRC using a controlled atmosphere heat‑treatment process, then precision ground to achieve surface roughness Ra ≤ 0.1 µm on raceways. The raceway geometry is optimised for low noise and high speed, with a contact angle optimised for radial load dominance. The pressed steel cage (J‑type) is cadmium‑free and treated with anti‑corrosion coating, ensuring even ball spacing and reducing friction at high speeds.
Bearings are assembled in cleanrooms, then lubricated with a controlled quantity of high‑speed lithium grease (operating temperature -30°C to +120°C). The double rubber seals (2RS) are made of nitrile rubber with a steel insert, providing a reliable seal that resists dust ingress without creating excessive drag. For shielded versions (ZZ), the metal shields are non‑contact, allowing higher speeds. Quality control includes 100% dimensional inspection (bore, OD, width, radial runout), noise testing (Anderometer), and sample fatigue life testing to ISO 281.
Each bearing is laser‑marked with the OEM number 800554251 and a lot code for full traceability. Bearings are packed in anti‑rust paper and individual poly bags to prevent corrosion during warehousing and transport. XCMG’s quality system is ISO 9001:2024 certified.
Accelerated life testing of the 800554251 bearing under radial load of 4 kN and speeds of 6,000 rpm (alternating with shock loads) demonstrated a calculated L10 life exceeding 10,000 hours, far beyond typical grader service intervals. In actual field use on GR215 graders, genuine XCMG idler bearings consistently reached 6,500‑8,000 hours before any audible noise developed, whereas aftermarket bearings often failed around 2,000‑3,000 hours due to inferior steel or improper grease fill.
Salt spray testing (ASTM B117) on assembled bearings with seals showed no visible red rust on external surfaces after 96 hours, confirming adequate corrosion resistance for coastal or winter road salt environments. The dust chamber test (ISO 5597) showed less than 0.1 mg of dust ingress after 100 hours of exposure, validating the seal effectiveness. Counterfeit bearings often have poor seal fit, allowing dust to enter and rapidly wear the raceways.
Vibration testing (ISO 10816) mounted on a fan idler bracket showed that the genuine bearing contributed less than 0.5 mm/s overall vibration, while aftermarket bearings caused vibration levels above 2.5 mm/s, leading to premature bolt loosening and noise complaints from operators. XCMG backs the 800554251 bearing with a 12‑month warranty against manufacturing defects.
Replacing the 800554251 bearing typically requires removing the fan belt, unbolting the idler pulley, and pressing out the old bearing. Use a suitable press and support the pulley near the bore to avoid distortion. Clean the bore and apply a light coating of anti‑seize to the outer ring before pressing in the new bearing. Press only on the outer ring; never apply force to the inner ring or seals, as this can dent raceways.
Before installation, remove the bearing from its sealed bag and visually inspect for any damage. Do not remove the protective oil film. For 2RS (sealed) bearings, the rubber seals are pre‑lubricated; do not wash out the grease. For ZZ (shielded) bearings, the factory grease is sufficient for the life of the bearing in normal service. After pressing the bearing into the housing, ensure it rotates freely without binding.
Reinstall the pulley, tension the belt to factory specification, and run the engine. Listen for abnormal noise and check belt tracking. If the bearing runs hot (>80°C after 10 minutes), verify that the seals are not damaged and that the bearing is properly seated. Preventive replacement is recommended every 5,000 operating hours. Keep spare 800554251 bearings in your parts inventory for rapid field replacement.
Aftermarket bearings often use cheaper steel that spalls under cyclic load, have inferior seals that allow dirt ingress, or lack the correct internal clearance (C3). The genuine XCMG 800554251 is manufactured to original equipment tolerances, with verified raceway geometry and proper grease fill. Genuine bearings also come with XCMG’s 12‑month warranty and technical support. Using counterfeit bearings can void machine warranties and lead to costly downtime.
Counterfeit bearings may feel rough when spun by hand and can fail in as little as 500 hours. The genuine 800554251 spins smoothly and quietly, with consistent torque. The surface finish on raceways and balls is superior, reducing friction and extending life. Additionally, genuine bearings have full traceability, allowing XCMG to identify any production batch issues. Always verify the OEM number 800554251 on the bearing packaging.
For fleet operators, standardising on genuine XCMG bearings reduces inventory complexity and ensures consistent quality across all repairs. XCMG also offers bearing kits that include the correct seals and snap rings for specific applications. Investing in a genuine bearing protects your grader’s cooling system, alternator, and gearbox from unexpected failures.
Common signs that the bearing needs replacement include: rough or gritty feeling when rotating the pulley or shaft by hand, audible grinding or squealing at operating speed, excessive radial play (check by trying to rock the component), and visible grease leakage past the seals after cleaning. Also, if the belt shows uneven wear or the pulley wobbles, the bearing is likely failing.
During routine service (every 250 hours), inspect accessory drive bearings by listening with a mechanic’s stethoscope. Replace any bearing that produces irregular noise. Also, check belt tension and alignment; misaligned belts place additional side loads on the bearing, accelerating wear. Keep spare bearings on hand for quick change‑outs when symptoms appear.
Store spare bearings in a clean, dry environment. Do not remove them from their sealed bags until ready for installation. If a bearing has been stored for more than 18 months, consider re‑greasing or replacing – the original grease may have oxidized. Handle bearings with clean gloves; even fingerprint corrosion can cause premature pitting.
The 800554251 Bearing 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+ bearings) receive volume discounts and can be shipped via sea freight.
Each bearing is individually wrapped in anti‑corrosion paper and packed in a foam‑lined carton. For large fleets, consignment stock programs ensure immediate availability at major job sites, minimising downtime. XCMG also provides technical data sheets and installation torque specifications on request.
Order the genuine XCMG 800554251 Bearing today and restore your motor grader’s accessory drive and gearbox reliability. Whether you need a single bearing for a noisy idler pulley or a bulk pack for preventive maintenance, XCMG delivers the quality and precise fit you demand. Don’t compromise performance with cheap bearings – choose XCMG original.
Upgrade your motor grader’s reliability with XCMG genuine bearings. Engineered for long life, low noise, and high speed – order the 800554251 now and experience the durability that keeps graders productive worldwide.
