Case-hardened alloy steel Ring Pinion and Crown Wheel & Pinion with 4.10:1 ratio for ISUZU NPR 4BG1 Truck Differential

A precision-forged hypoid gear set that transmits engine torque from the propeller shaft to the rear axle shafts, providing final speed reduction and torque multiplication for heavy-duty Isuzu NPR trucks.

The Ring and Pinion Gear Set (OEM Numbers: 1-41210417-0 / 1412104170), also known as a crown wheel and pinion or final drive gear set, is a premium-quality, direct replacement differential component engineered specifically for the ISUZU NPR series medium-duty trucks powered by the legendary 4BG1 4.3L diesel engine.

As the heart of the rear axle assembly, this hypoid gear set is responsible for the final reduction of rotational speed and the multiplication of torque before it is transmitted to the wheels, directly impacting vehicle acceleration, load-pulling capability, and driveline efficiency.

• High-Strength Alloy Steel: Forged from premium SAE 8620/4320 alloy steel, heat-treated for exceptional core toughness and surface hardness
• Precision Matched Set: Each pinion and ring gear are lapped together as a set with matching numbers
• Hypoid Spiral Bevel Design: Provides smooth, efficient torque transfer with higher load capacity
• Crown Wheel Features: Precision-drilled bolt holes for secure mounting to differential case
• Drive Pinion Features: Integrated spline shaft for direct fit to differential yoke
• Heavy-Duty Design: Engineered for stop-start cycles and load-hauling duties

• Material verification via spectrographic analysis
• Dimensional accuracy verified against OE blueprints using CMM equipment
• Tooth profile inspection using dedicated gear checking equipment
• Hardness testing via Rockwell testing on batch samples
• Lapping & contact pattern check for proper tooth bearing
• Runout measurement to guarantee concentric mounting
• ISO 9001:2015 / IATF 16949 Certified facility
• 100% visual inspection before shipment

Each ring and pinion set is anti-corrosion oil-coated, individually sealed in moisture-barrier VCI bag, and boxed with OE-style part labeling.

Available for wholesale/bulk orders with case packs of 5, 10, 20, 50 sets. Custom packaging and fast worldwide shipping available.