5/8" Bore Size Precision-Honed Hydraulic Clutch Master Cylinder Assembly with High-Quality Fluid-Resistant Seals for HINO 300 Dutro XZU N04C

The Clutch Master Cylinder Assembly (OEM Number: 31420-37141) is a premium-quality, direct replacement hydraulic component designed for HINO 300 Series and Dutro trucks (including XZU models). This precision-engineered master cylinder converts mechanical force from the clutch pedal into hydraulic pressure, enabling smooth clutch engagement and disengagement.

• OE Quality: Manufactured to strict HINO/Toyota dimensional and performance specifications for perfect fit and function
• Precision Honed Bore: 5/8" (15.87mm) bore ensures smooth piston travel and consistent hydraulic pressure
• Durable Construction: High-quality housing resists corrosion and wear for long service life
• Reliable Seals: Fluid-resistant seals prevent leaks and maintain hydraulic pressure
• Smooth Clutch Operation: Enables precise, responsive clutch control
• Restores Shifting Performance: Eliminates spongy pedal feel and shifting difficulties
• Direct Replacement: Simple installation during clutch system service
• Long Service Life: Engineered for reliability in demanding commercial applications
• Cost-Effective Maintenance: Essential component for reliable clutch system performance

This clutch master cylinder assembly is specifically designed for HINO trucks and compatible models:

• HINO 300 Series – Light to Medium-Duty Trucks
• HINO Dutro – Light to Medium-Duty Trucks
• HINO XZU Series – XZU304R, XZU305R, XZU307, XZU710L, XZU710R, XZU720L, XZU720R, XZU433R, XZU413L
• HINO XZC Series – XZC730R
• HINO WU Series – WU422L, WU720L

• N04C – 4.0L 4-Cylinder Diesel
• N04C-T – Turbocharged Variant
• N04C-WU / N04C-WG – Variants
• W04D – 4.0L Diesel

• Toyota Dyna – Light to Medium-Duty Trucks
• Toyota ToyoAce – Light to Medium-Duty Trucks

1. Disconnect battery – Disconnect the negative battery cable before beginning work
2. Drain clutch fluid – Drain the clutch fluid from the reservoir and system
3. Disconnect hydraulic line – Carefully disconnect the clutch fluid line from the master cylinder
4. Remove the old master cylinder – Unbolt and remove the old master cylinder from the firewall
5. Inspect the pushrod and pedal linkage – Check for wear or damage; replace if necessary
6. Clean the mounting area – Clean the firewall mounting surface and surrounding area
7. Prepare the new master cylinder – Inspect the new cylinder and verify it matches the original
8. Install the new master cylinder – Position the new cylinder and secure with mounting bolts
9. Torque to specification – Tighten bolts to manufacturer specification
10. Connect hydraulic line – Reconnect the clutch fluid line to the master cylinder
11. Fill reservoir – Fill the reservoir with the correct type of clutch/brake fluid
12. Bleed the system – Bleed the hydraulic clutch system to remove all air from the lines
13. Check pedal feel – Test the clutch pedal for proper feel and travel
14. Reconnect battery – Reconnect the battery
15. Test operation – Start the engine and test clutch engagement and shifting
16. Road test – Test drive the vehicle to verify smooth clutch operation

• Material Verification: Confirms housing and seal materials meet OE specifications
• Dimensional Inspection: Bore size (5/8"), mounting dimensions, and port positions verified against OEM tolerances
• Leakage Testing: 100% pressure-tested for internal and external fluid leakage
• Piston and Seal Inspection: Seal integrity and piston smoothness verified for reliable operation
• Surface Finish Inspection: Machined surfaces checked for proper finish
• Visual Inspection: 100% checked for casting defects, machining flaws, or damage
• Packaged Safely: Protected and securely packaged to prevent contamination and damage during transit

• 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