1" Bore Grey Cast Iron Corrosion-Resistant Clutch Slave Cylinder Assembly for Isuzu NPR NKR NQR NPS

Clutch Slave Cylinder 8-97032849-1 for Isuzu N-Series NPR NKR — 8970328491

The Clutch Slave Cylinder with OEM reference numbers 8-97032849-1 and 8970328491 is a verified direct-fit replacement for a wide range of Isuzu N-Series trucks, including NKR, NPR, NQR, and NPS models. This hydraulic component is a critical part of the clutch actuation system, converting hydraulic pressure from the clutch master cylinder into mechanical force that engages and disengages the clutch.

The slave cylinder is mounted externally on the transmission housing, where its piston extends to push the clutch fork, which in turn operates the release bearing. A failing clutch slave cylinder typically presents with a soft or spongy clutch pedal, difficulty shifting gears, fluid leaks around the cylinder, or the clutch pedal sticking to the floor — all of which can leave a commercial vehicle stranded.

This OE‑spec replacement cylinder is manufactured from high-grade grey cast iron with a precision-honed 1" (25.4mm) bore, featuring a hard-anodized piston, high-quality EPDM rubber seals, and an electrophoresis-coated exterior for superior corrosion resistance. It restores factory clutch pedal feel and hydraulic performance, ensuring smooth and reliable gear changes for your Isuzu truck.

Primary Applications (Isuzu N-Series):

Additional Compatible Applications:

Engine Compatibility:

• Isuzu 4JB1, 4BD2, 4JA1
• Isuzu 4HF1
• Isuzu 4BE1, 4BD1

When to replace your clutch slave cylinder:

• Soft or spongy clutch pedal — indicates internal seal failure or fluid bypass
• Difficulty shifting gears — incomplete clutch disengagement
• Clutch pedal sticking to the floor — piston seizure or internal damage
• Visible fluid leak — around the cylinder or from the dust boot
• Low clutch fluid level — with no external leak visible (internal leakage)
• Clutch chatter or judder — inconsistent hydraulic pressure

Installation Guidelines (Reference Isuzu workshop manual for complete steps):

1. Safety first — securely support the vehicle on jack stands
2. Locate the slave cylinder on the transmission housing
3. Disconnect the hydraulic line from the slave cylinder
4. Remove the mounting bolts securing the cylinder
5. Remove the old cylinder from the vehicle — note the push rod orientation
6. Compare the new cylinder with the old unit — verify bore size (1"), mounting hole alignment, and push rod length
7. Install the new slave cylinder into the mounting hole in the transmission housing
8. Torque mounting bolts to manufacturer specification
9. Reconnect the hydraulic line — ensure proper thread engagement
10. Bleed the clutch hydraulic system — use a vacuum bleeder or two-person method; start from the slave cylinder bleeder valve
11. Check clutch pedal feel — should be firm with proper free play
12. Test drive — verify smooth gear changes and no fluid leaks

Pro Tips:

• Do not depress the clutch pedal after removing the slave cylinder — this can push the piston out of the cylinder
• Apply a thin layer of copper grease to the contact surface for the push rod
• When replacing the slave cylinder, inspect the clutch master cylinder and hydraulic line for wear
• If the slave cylinder has failed due to contaminated fluid, flush the entire hydraulic system

Maintenance Schedule:

• Inspect the slave cylinder and hydraulic line for leaks at every service interval
• Replace clutch fluid every 2 years or 50,000 km to prevent moisture contamination and internal corrosion
• If replacing the slave cylinder, consider replacing the master cylinder simultaneously for balanced hydraulic performance