Clutch Slave Cylinder 8-97941515-0 8979415150 For ISUZU D-MAX TFR TFS 4JJ1 4JK1 4JH1 (2003–2011) — Concentric Type, Ø20.6mm Bore, Cast Iron, 98mm Mounting

The Clutch Slave Cylinder with OEM references 8-97941515-0 / 8979415150 is a verified direct-fit hydraulic component for ISUZU D-MAX (TFR/TFS) pickups built between 2003 and 2011, covering the 4JJ1-TC (3.0L), 4JK1 (2.5L), and 4JH1 diesel engines. ISUZU's official parts system confirms this as a genuine ISUZU "CYLINDER; SLAVE" — identical to the unit mounted at the factory when the vehicle was new — with a reference price of €68.57 ex-tax.

This is a concentric clutch slave cylinder (CSC) — a design that combines the functions of the clutch release bearing and the hydraulic slave cylinder into a single integrated unit. Unlike conventional external slave cylinders that push a release fork, this unit mounts directly around the gearbox input shaft and acts directly on the clutch diaphragm spring. This architecture eliminates the release fork, pivot, and bearing as separate wear items, delivering more direct, consistent clutch release with fewer components to fail.

The cylinder is manufactured from cast iron (Ghisa / Fonte), with a Ø20.6 mm piston bore, 98 mm mounting hole distance, 2 mounting holes, and a 1 × M10×1.0 connection thread. Reference weight is 0.850 kg (OE reference) / 0.97 kg (A.B.S. aftermarket).

• OEM Genuine Status Verified: 8979415150 is confirmed by parts-isuzu.com as a genuine ISUZU part ("exactly the same as factory"), with reference price €68.57 ex-tax.
• Concentric CSC Architecture Verified: "The concentric clutch slave cylinder combines the functions of the thrust bearing and of the clutch cylinder in a single part" — confirmed by Brembo technical documentation for E 34 005.
• Bore Diameter Verified: Ø20.6–20.64 mm — confirmed by AUTODOC (LPR 3154, Brembo E 34 005: 20.64 mm; A.B.S. 71757: 20.6 mm) and Herth+Buss J2609002 (13/16″ ≈ 20.6 mm).
• Mounting & Thread Verified: 98 mm mounting hole distance, 2 mounting holes, 1 × M10×1.0 thread — confirmed by AUTODOC (A.B.S. 71757 specifications).
• Material Verified: Cast Iron (Ghisa / Fonte) — confirmed by AUTODOC (LPR 3154, Brembo E 34 005, A.B.S. 71757).
• Weight Verified: 0.850 kg (OE/Blue Print reference) / 0.97 kg (A.B.S. 71757).
• Vehicle & Engine Coverage Verified: ISUZU D-MAX 2003–2011, engines 4JJ1-TC (3.0L), 4JK1 (2.5L), 4JH1 — confirmed by eBay fitment data and Ecer/Yimi factory listings.
• Cross-Reference Density Verified: 8979415150, 8-97941515-0, 97941515, 8979451770, 5876100800, 8979477650, 5876100801, 8979445133 are consistently grouped across ISUZU, Blue Print, AISIN, Herth+Buss, Brembo, and LPR catalogs.
• Brand Cross-Reference Verified: AISIN CRG-902, Blue Print ADZ93622, Herth+Buss JAKOPARTS J2609002, Brembo E 34 005, LPR 3154, A.B.S. 71757, KAVO PARTS CCS-3503, TRW PJF900, JAPANPARTS CY-900.

• Clutch pedal sinks to the floor or feels spongy: Internal seal failure within the concentric cylinder allows hydraulic pressure to bypass, preventing full clutch disengagement — the most common symptom of a failing CSC.
• Difficulty selecting gears / gear clash: Insufficient hydraulic pressure means the clutch does not fully disengage, causing hard shifting and gear grinding.
• Fluid leak at the gearbox bellhousing: A failed CSC seal allows clutch fluid to escape into the bellhousing, often visible as wetness or drips at the gearbox-engine joint.
• Clutch pedal does not return fully or has a low engagement point: A worn internal seal or release mechanism prevents the pedal from returning to its rest position.
• Fluid level dropping in the clutch reservoir without an external leak: Internal seal bypass can allow fluid to enter the bellhousing or the hydraulic circuit.
• Noise or vibration when depressing the clutch: A worn thrust bearing surface within the CSC can produce noise or vibration during clutch operation.

• Concentric vs. external: This is a concentric CSC mounted inside the bellhousing around the input shaft. It is not an external slave cylinder that pushes a release fork. Do not substitute an external cylinder — the gearbox and clutch release mechanism are different.
• Engine variant: The CSC is confirmed for 4JJ1-TC, 4JK1, and 4JH1 diesel engines. Confirm the engine code and VIN before ordering, especially for fleet applications with mixed engine types.
• Model year boundary: The confirmed window is 2003–2011. Later D-MAX generations (2012+) may use a different clutch release architecture. Do not assume interchangeability across the 2011/2012 boundary without VIN confirmation.
• Hydraulic line connection: The M10×1.0 connection must match the vehicle's clutch line fitting. Confirm the line thread specification against the original unit.

1. 1Confirm the required part first: Verify that the original unit is a concentric CSC (mounted around the input shaft), not an external slave cylinder. Confirm the Ø20.6 mm bore and 98 mm mounting hole distance.
2. 2Safety first: Park on level ground, engage the parking brake, and chock the wheels. Disconnect the battery negative terminal.
3. 3Remove the gearbox: Support the gearbox with a transmission jack and separate it from the engine. Do not let the gearbox hang on the input shaft — this can damage the clutch and CSC.
4. 4Remove the old CSC: Unbolt the CSC from the bellhousing/input shaft guide tube. Note the orientation and any shims or seals. Inspect the input shaft guide tube for wear — a worn guide tube will damage the new CSC seal.
5. 5Inspect the clutch assembly: With the CSC removed, inspect the clutch diaphragm spring and release bearing surface for wear. If the clutch is worn, replace it as a complete kit (clutch disc, pressure plate, and CSC).
6. 6Install the new CSC: Position the 8-97941515-0 CSC onto the input shaft guide tube. Lubricate the seal lip with clean clutch fluid (not grease). Secure the mounting bolts to the workshop manual specification.
7. 7Reinstall the gearbox: Mate the gearbox to the engine, ensuring the input shaft engages the clutch disc splines smoothly. Do not force the gearbox into place.
8. 8Bleed the clutch system: Fill the reservoir with the specified clutch fluid and bleed the system according to the ISUZU procedure until clear, bubble-free fluid flows from the bleeder screw. Air in the circuit is the leading cause of post-replacement clutch drag.
9. 9Test operation: With the engine running, depress the clutch pedal and verify smooth gear engagement in all gears. The pedal should return fully and the vehicle should not creep when a gear is selected with the clutch depressed.

• Inspect clutch fluid level at every engine oil change — a dropping level indicates a leak that requires immediate attention.
• Flush clutch fluid every 2 years or according to the ISUZU schedule — degraded fluid accelerates seal wear in the CSC.
• Replace the CSC whenever the clutch is replaced — the CSC bearing surface wears in tandem with the clutch, and reusing an old CSC with a new clutch is a false economy.
• Inspect the input shaft guide tube during any gearbox removal — a worn guide tube will cause repeat CSC seal failure.

• Standard packing: Neutral carton or customer-requested packaging.
• Package contents: 1 × Clutch Slave Cylinder (Concentric CSC). Mounting bolts, bleeder screw, and clutch fluid are not included unless explicitly stated — confirm exact package contents at inquiry.
• Set options: CSC only (standard) / CSC + clutch kit (disc + pressure plate + CSC) — specify at inquiry.
• Suitable for: ISUZU D-MAX clutch and gearbox repair shops, light commercial fleet maintenance departments, spare parts distributors, and export wholesalers serving Southeast Asia, the Middle East, Africa, and Latin America.
• Related parts available: Clutch disc, pressure plate, release bearing (if external), clutch master cylinder, clutch fluid, and complete D-MAX clutch hydraulic service kits.