New Clutch Master Cylinder 1-1/8-inch bore size 29785C FE27129
Bexar Pro Components: Heavy-Duty Reliability for Fleet & Industry.
Key Specifications & Expert Features
- Bore Diameter: 1-1/8-inch bore size (Critical for vehicle and equipment pressure calibration)
- Outlet Size: (2) 1/8″-27 (Dual ports for versatile hydraulic line connection)
- Application: Engineered for medium-duty trucks, commercial fleets, and heavy industrial machinery.
- Companion Repair Kit: 376MK (View Compatible Kit)
- Cross-Reference: For the brake master version using this same casting, see M3606330.
Verified Casting & Part Numbers
Matching your existing casting number is the most reliable method to ensure correct fitment. This unit replaces:
- 29785C
- FE27129
- FE20932
- 1556659
- 2265633
- 5461342
- 27129
- 28818C
- 616648
Expert Installation & Field Note
Based on our shop experience specializing in heavy-duty brakes since 1985: When installing the CM3283971, proper seal lubrication and linkage alignment are the leading factors in preventing premature wear. If using the 376MK repair kit, do not install a check valve in the master cylinder unless your original core specifically used one; doing so can cause pressure trap issues. Always bench bleed the unit before final installation to ensure the 1-1/8-inch bore galleries are free of air for a smooth, consistent pedal feel.
⚠ CRITICAL: Verify Specifications
To ensure proper clutch engagement pressure and safety, it is absolutely critical to physically verify that this master cylinder’s 1-1/8-inch bore size and 1/8″-27 outlet size match your existing unit exactly. Accurate displacement is required for proper function in all automotive and industrial drivetrains.








