High-Strength Steel Heat-Treated Driving Pinion Nut OEM Standard for Isuzu NPR66 4HF1 Differential

• OE Quality: Manufactured to Isuzu dimensional and material specifications for perfect fit and reliable pinion retention
• High-Strength Steel: Heat-treated to withstand high torque and axial loads
• Precision Threads: Ensures consistent torque application and secure fastening
• Restores Differential Integrity: Eliminates pinion looseness, gear noise, and bearing failure
• Direct Replacement: Matches OE thread and hex size
• Cost-Effective: Affordable alternative to genuine OEM nuts

This driving pinion nut is specifically designed for Isuzu NPR66 trucks with 4HF1 engine.

• ISUZU NPR66 (medium-duty truck, 4HF1 engine)
• May also fit other Isuzu models with similar differential - verify compatibility

• 4-Cylinder, Inline Diesel, Direct Injection
• Displacement: 3.9L (3856cc)

Installation steps (overview for pinion nut installation):

1. Install the drive pinion with new bearings and crush sleeve into the differential housing
2. Install the pinion flange and new pinion nut
3. While rotating the pinion, torque the nut gradually to set pinion bearing preload
4. Measure pinion rotating torque using an inch-pound torque wrench - adjust until within OE specification
5. Do not back off the nut to reduce preload - if over-torqued, replace the crush sleeve and start over
6. Stake or lock the nut as per OE procedure

• Material Verification: Steel composition and hardness tested
• Dimensional Inspection: Thread pitch, hex size, and overall dimensions verified
• Thread Gauge Inspection: GO/NO-GO thread verification
• Visual Inspection: 100% checked for defects
• Packaged Safely: Sealed in plastic bag, boxed with foam

• Neutral export packing or customized packaging available
• Carton or wooden case for safe transportation
• Fast delivery for stock items
• Shipping by Express Air or Sea