clutch cylinder,brake cylinder,hydraulic clutch release bearing FAQ

FAQ

1. Basic Product Knowledge

Q1: What is a hydraulic concentric slave cylinder (CSC)? What is the difference between CSC and traditional clutch slave cylinder?

A: A hydraulic CSC (Concentric Slave Cylinder) is an integrated unit that combines a clutch release bearing and a slave cylinder in one single component.

• Traditional structure: External clutch slave cylinder + release fork + separate release bearing

• CSC structure: Installed inside the transmission, eliminating the release fork. It features a more compact structure and is widely used in modern passenger cars, SUVs and light pickup trucks.

Note: CSC and traditional slave cylinders are not interchangeable. Please match strictly by OE number and vehicle model.

Q2: Can clutch pumps and brake pumps be used interchangeably?

A:No, never interchangeable.

1. Fluid specification differs: Clutch systems use DOT3/DOT4 brake fluid with different working pressure requirements;

2. Internal seal material, cylinder bore size, piston stroke and thread specifications are different;

3. Mounting brackets and port connections do not match.

Mixing them will cause pressure leakage, clutch failure or even brake failure, leading to serious safety hazards.

Q3: What parts are included in the standard package?

• Clutch & Brake Master Cylinder: Main body, dust cover, push rod, sealing ring, mounting gasket (for partial models)

• Clutch & Brake Wheel Cylinder: Piston, dust boot, rubber cup, bleeder screw

• CSC Hydraulic Release Bearing: All-in-one integrated assembly (bearing + cylinder + connector), non-detachable and non-repairable

Repair kits are available for separate inquiry if required.

2. Model Matching & Selection

Q4: How to confirm if the part fits my vehicle?

A: Please provide one of the following for accurate matching (priority from high to low):

1. Original OE number (most accurate)

2. Vehicle VIN code

3. Car model + production year + engine type + transmission type (MT / DCT)

Tips: Do not confirm fitment only by car name. The same model may have different factory specifications for domestic and overseas versions, resulting in different replacement parts.

Q5: Why do parts with the same OE number look different from different factories? Are they interchangeable?

A: Automakers usually adopt multiple suppliers for original supporting parts.

As long as the OE number, mounting dimensions, thread size and piston stroke are consistent, the parts are functionally interchangeable. Minor appearance differences do not affect installation and performance. We can provide real photos for confirmation before ordering.

Q6: Do hydraulic release bearings (CSC) have left/right distinctions?

A: Most CSC models are universal with no left/right difference. Only a few specific vehicle models have directional housing and pipe port differences. Please confirm photos and OE numbers before purchase.

3. Material & Performance Specifications

Q7: What are the cylinder body materials?

• Modern clutch master cylinders and CSC units: Aluminum alloy, lightweight and anti-rust

• Traditional brake wheel cylinders & heavy-duty truck cylinders: Cast iron

• Standard seal material: EPDM rubber, compatible with DOT3/DOT4 brake fluid, oil-resistant and anti-expansion.

Q8: What is the working pressure and temperature range?

• Normal working pressure: 0.8–3.5 MPa

• Operating temperature: -40℃ ~ +120℃

• Compatible with DOT3 & DOT4 brake fluid.Do not use DOT5 silicone brake fluid, which will damage internal seals.

Q9: Are your parts OEM quality or aftermarket quality?

A: All products are manufactured strictly according to OE standards for the global aftermarket. Every unit is 100% pressure and leakage tested before delivery to ensure zero oil leakage and stable performance.

4. Installation & Troubleshooting

Q10: Newly installed clutch pump / CSC has soft pedal and pressure loss. What causes this?

A: Main reasons as below:

1. Incomplete air bleeding (most common. Built-in CSC structure requires more careful bleeding than traditional cylinders)

2. Wrong brake fluid type causing seal swelling and failure

3. Incorrect push rod clearance adjustment

4. Missing sealing gasket or loose thread connection causing leakage

Suggestion: Bleed the hydraulic system strictly per repair manual and replace with qualified new brake fluid.

Q11: Why does the hydraulic release bearing make abnormal noise?

1. Insufficient bearing lubrication (New products are pre-lubricated before delivery)

2. Wear of clutch pressure plate or release lever (not caused by bearing failure)

3. Skewed installation leading to eccentric force on the bearing

Note: CSC is an integrated non-serviceable assembly. The whole unit needs replacement once damaged.

Q12: Brake wheel cylinder piston cannot return normally and causes dragging brakes.

1. Rust or insufficient lubrication on guide pins

2. Stuck or aging sealing rings

3. Blocked brake hose

It is recommended to clean guide pins and apply special anti-noise grease during installation.

Q13: Where do oil leakage usually occur?

1. Dust cover position: Worn main cylinder piston seals

2. Bleeder screw position: Loose screw or damaged gasket

3. Hose thread interface: Poor sealing

4. CSC housing seam: Rare factory casting defects (100% inspected before shipment)

5. Business & Shipping Policy

Q14: What is your packaging standard? Can you support neutral packaging or custom private labeling?

A: Standard package: Independent color box / neutral white box. Custom color boxes and private label stickers are available based on MOQ. Outer package: Standard 5-layer export carton.

Q15: What is the MOQ? Can I mix different models for one order?

A: Sample orders with small quantity are acceptable for regular models. Mixed loading of multiple models is supported for bulk orders. Hot-selling models are in stock for fast delivery.

Q16: What is your warranty policy?

A: We provide professional warranty under standard installation and normal driving conditions.

Warranty Exclusions: Damage caused by improper installation, incomplete air bleeding, inferior brake fluid, traffic accidents or modified overloading is not covered by warranty.

Q17: Can I get samples? Who bears the sample and freight cost?

A: Sample testing is available. Sample fee and freight cost are borne by the buyer. The sample fee can be partially or fully deducted from future bulk orders upon negotiation.

6. Storage & Transportation

Q18: How to store the products during long sea transportation?

A: All products are well-sealed and dust-proof before delivery. Please store in dry and ventilated environments. Avoid long-term exposure to humid air to prevent interface rust. Please check dust cover integrity after receiving goods.

Q19: Are the pumps filled with brake fluid before shipment?

A:No brake fluid is pre-filled.

We only apply protective lubricating grease for internal seals to avoid fluid leakage and seal damage during long-distance transportation. Please fill with qualified brake fluid and bleed the system after installation.

7. Concept Distinction & Supplement

Q20: Is CSC hydraulic release bearing equal to a clutch slave cylinder?

A: Not exactly.

Traditional external clutch slave cylinder is a separate outer part; CSC (Concentric Slave Cylinder) is an integrated internal clutch slave bearing cylinder. They have different structures and cannot be interchanged.

Q21: Do dry DCT transmissions need hydraulic release bearings?

A: Some dry dual-clutch transmissions adopt hydraulic CSC systems, while others adopt electric motor drive. Please confirm the exact transmission type before ordering.

FAQ