Brakes› Master Cylinders-Boosters and Components
ACDelco
1-Inch Bore Brake Master Cylinder
SKU: 18M938
Moderate — 2–4 hours
Description
This master cylinder is manufactured to meet expectations for fit, form, and function, utilizing both aluminum and iron castings. It contains Ethylene Propylene (EPDM) and Styrene Butadiene (SBR) rubber components for superior resistance to heat, corrosion, and leakage. The unit is ready for installation without requiring assembly.
Fitment
Fitment Guaranteed
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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.
Available on iOS & Android
Specifications
| Brand | ACDelco |
| Part Number | 18M938 |
| Category | Brakes |
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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