B57Z-7A Double Z Metal Shield Auto Gearbox Deep Groove Bearing
B57Z-7A non-standard deep groove ball bearing, dimension 57.7×80×13mm, upgraded version of B57Z-7 for car automatic transmission auxiliary shafts. Double-sided stamped Z metal dust shields without rubber seals, matched stamped steel cage and C0 standard clearance. It bears radial load and minor bidirectional axial load, runs stably and low-noise under long-term high-speed shifting vibration. Made of fully quenched high-purity GCr15 chrome steel with tighter dimensional tolerance control, fully interchangeable with original OEM B57Z-7A. Complete formal quotation will be provided within 24 hours upon inquiry.
- All-metal Z shields resist high gear oil temperature, no rubber seal aging, swelling or leakage risk under long-time high-temperature oil soaking
- Tiny clearance between metal shields allows smooth gear oil circulation inside gearbox, outstanding heat dissipation
- Superfinished deep groove raceway reduces rolling friction, stable continuous operation under frequent shifting impact
- Uniform high-hardness GCr15 steel delivers excellent wear and anti-fatigue performance to extend gearbox service life
- Upgraded tolerance control improves assembly precision, direct replacement without modifying gearbox housings or shafts
- Lightweight stamped steel cage lowers rotation inertia, adapts to medium-high speed continuous transmission working conditions
- Standard P0 precision grade, customizable P6 clearance to meet automotive OEM assembly standards
Passenger car automatic gearbox intermediate & auxiliary shafts, small CVT transmission assemblies, light commercial vehicle reducers, mini agricultural machinery transmission parts.
| Model | B57Z-7A Double Z Metal Shield Deep Groove Ball Bearing |
| Inner bore d | 57.7 mm |
| Outer diameter D | 80 mm |
| Width B | 13 mm |
| Seal structure | Double-sided Z stamped metal dust shields, oil lubrication only |
| Cage | Stamped low carbon steel cage |
| Internal clearance | C0 standard clearance |
| Material | High-purity GCr15 chrome bearing steel |
| Basic dynamic load | 29.3 kN |
| Basic static load | 20.1 kN |
| Max oil lubrication limiting speed | 4500 r/min |
| Net weight | 0.28 kg |
| Working temperature range | -20℃ ~ +130℃ |
| Accuracy grade | P0 standard, P6 customizable |
| Cross reference | B57Z-7A, B57Z-7 |
Dimension drawings and technical spec sheets can be provided on request.
25+ years professional manufacturer of Z shield non-standard automotive gearbox bearings. All finished bearings pass metal shield oil aging test, high-speed continuous rotation test and shock fatigue durability test before delivery. Support customized anti-rust surface coating and special high-temperature gearbox lubricant filling service. One-on-one professional installation technical guidance and formal quotation within 24h for all RFQs. Stable mass production capacity meets bulk OEM and global distributor orders, factory direct selling price, stable consistent quality and punctual batch delivery.
- Raw GCr15 steel hardness & chemical composition incoming inspection
- High-precision raceway superfinishing roughness detection
- Z metal shield high-temperature gear oil circulation aging test
- Continuous vibration load rotation fatigue life test
- Full dimension tolerance sorting inspection
- 100% visual appearance marking check before packaging
- Random sampling high-speed performance test before shipment
All B57Z-7A bearings pass multi-process strict factory inspection.
Send bulk inquiry for B57Z-7A double Z shield transmission bearings and obtain the following support:
- Complete formal detailed quotation within 24 hours
- Standard dimension drawings & press-fit installation operation guidance
- Custom anti-rust surface treatment and special transmission lubricant filling service
- Exclusive long-term bulk factory wholesale price without intermediate markup
Large-volume OEM cooperation is welcome anytime.
Q1: What’s the difference between B57Z-7A and B57Z-7?
A1: B57Z-7A adopts tighter dimensional tolerance control, higher roundness and surface precision, fits high-precision automatic gearbox matching requirements.
Q2: Difference between Z metal shield and rubber sealed bearing?
A2: Double Z all-metal shield withstands high oil temperature, designed for internal gearbox oil circulation environment; rubber sealed bearings apply to external dusty shafts with grease lubrication.
Q3: Can B57Z-7A replace original OEM bearings directly?
A3: Yes, inner bore, outer diameter, width and shield structure sizes are fully consistent, no modification to gearbox components required during replacement.
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