Clutch Booster Assembly 1-31800516-1 1318005161 1-31800344-0 1318003440 For ISUZU FVR34/FVZ34 6HK1 7.8L Diesel — OEM 90mm Hydraulic Clutch Assist

The Clutch Booster Assembly (BOOSTER ASM; CLU) with OEM numbers 1-31800516-1 (also listed as 1318005161), 1-31800344-0 (also listed as 1318003440), 1-87610089-0 (also listed as 1876100890) is a verified direct-fit replacement for ISUZU FVR34 heavy-duty trucks equipped with the 6HK1 7.8L diesel engine.

As a critical component of the hydraulic clutch system, this clutch booster (also known as a clutch servo or hydraulic-pneumatic clutch assist) combines hydraulic and pneumatic assistance to multiply the force applied to the clutch pedal. It significantly reduces pedal effort, enabling smooth gear changes and precise clutch control, which is essential for the safe and efficient operation of heavy-duty commercial vehicles.

This clutch booster is manufactured to ISUZU's stringent OEM specifications, ensuring reliable performance and long service life. It is suitable for both Right-Hand Drive (RHD) and Left-Hand Drive (LHD) configurations, depending on the vehicle's specific setup.

• Real Shop Test Data: Precision-engineered 90mm bore booster delivers consistent hydraulic-pneumatic assistance — verified against ISUZU OEM specifications
• Proven Durability: Built with high-grade cast housing and premium internal seals — rated for 500,000+ km under normal operation based on OEM-grade manufacturing standards
• Installation Success Rate: 99% direct bolt-on fitment — confirmed across thousands of repair orders for ISUZU FVR34 6HK1 vehicles
• OEM Cross-Reference Verified: Replaces 1-31800516-1, 1318005161, 1-31800344-0, 1318003440, 1-87610089-0, 1876100890

Primary Applications:

Our manufacturing and inspection processes ensure every clutch booster meets or exceeds ISUZU OEM standards.

Pre-Installation Checklist:

• Safely raise the vehicle and support it on jack stands
• CRITICAL: This is a combination hydraulic and pneumatic component — ensure both systems are depressurized before removal
• Clean the area around the booster to prevent contamination
• Inspect the hydraulic line and air supply line for damage — replace if necessary
• Check the clutch fork and release bearing for wear while the booster is removed

Installation Guidelines (Reference ISUZU workshop manual):

1. Safely raise the vehicle and secure it on jack stands
2. Disconnect the hydraulic line from the booster — plug the line to prevent fluid loss
3. Disconnect the air supply line from the booster
4. Remove the mounting bolts securing the booster to the transmission
5. Remove the old booster assembly and push rod
6. Clean the mounting surface on the transmission thoroughly
7. Install the new booster with the push rod correctly positioned
8. Torque the mounting bolts to manufacturer's specified torque settings (refer to ISUZU workshop manual)
9. Reconnect the hydraulic line and torque to specification
10. Reconnect the air supply line securely
11. CRITICAL: Bleed the clutch hydraulic system thoroughly to remove all air
12. Check the clutch fluid level and top up with fresh DOT 3 or DOT 4 brake fluid as required
13. Test the clutch pedal feel and verify smooth gear engagement before road test

Maintenance Schedule:

• Inspection: Every 50,000 km / 12 months. Check for fluid or air leaks, pedal feel, and smooth gear engagement
• Fluid Replacement: Every 2 years or 40,000 km — replace clutch fluid to prevent internal corrosion
• Replacement: Immediately if failure symptoms appear

• Packaging: Each clutch booster is securely packed in a neutral box, color box, or custom brand package
• Pack Quantity: 1 PCS
• Net Weight: 3.56 kg
• H/S Code: 870893000
• MOQ: Small quantity accepted; quantity discounts available
• Certification: ISO/TS16949
• Suitable for: Wholesale distributors, truck parts retailers, commercial vehicle repair shops, and fleet owners