Luk LMC108 Clutch Master Cylinder

Clutch Master Cylinder for BMW Manual Transmissions

This LuK clutch master cylinder is a new hydraulic replacement for BMW manual transmission applications. Built with an aluminum body, a 19.05 mm (0.750 in.) bore, and a female connector, it supports consistent clutch pedal hydraulic transfer for select BMW 3 Series and 5/6/M models.

Part number LMC108 is a direct-fit style replacement for vehicles such as the BMW 325i, 318i, and M3, with fitment coverage spanning 1982-1993 across the listed applications. LuK’s background in hydraulic clutch release systems is reflected in this component’s OE-style design approach.

Key Features

• LuK clutch master cylinder, part number LMC108
• Aluminum construction for hydraulic clutch service
• 19.05 mm / .750 bore diameter
• Female connector gender
• Push rod included
• Installation instructions included
• New part, not remanufactured
• Reservoir not included
• Pre-filled fluid: no
• Pre-bled system: no
• Clutch slave cylinder not included

Detailed Description

The LMC108 clutch master cylinder is designed for manual transmission clutch hydraulic systems that require a 19.05 mm bore and female connection. Its aluminum housing supports a lightweight, corrosion-resistant design, while the included push rod and installation instructions help streamline replacement work. This unit is supplied without a reservoir, without pre-filled fluid, and without a clutch slave cylinder, so it is suited for service jobs where those components are reused or sourced separately.

Compatible With BMW 325i, BMW 318i, BMW 325is, BMW 325iX, BMW M3, BMW 635CSi, BMW 528e, BMW 535i, BMW 535is, BMW M5, BMW M6, BMW 325e, BMW 325es, and BMW 533i applications listed in the fitment data. This part cross-references Dorman - First Stop CM39660 and Sachs SH5103 for the same application.

Common Problems This Part Can Address

• Soft or inconsistent clutch pedal feel
• Hydraulic fluid leakage at the master cylinder
• Difficulty disengaging the clutch
• Pedal travel that does not return normally
• Loss of hydraulic pressure in the clutch system

Installation Notes and Tips

Verify bore diameter, connector style, and vehicle fitment before installation. Because this unit is not pre-filled or pre-bled, the hydraulic system will need to be filled and bled after installation. Inspect the clutch line, pedal linkage, and slave cylinder condition during service to avoid repeat repairs. Use the included installation instructions as the primary reference for vehicle-specific steps.

Quality Assurance

LuK has extensive experience in hydraulic clutch release systems, and Schaeffler’s engineering background supports the design and application coverage of this replacement master cylinder. Part number LMC108 is a new component built for manual transmission service on select BMW models.