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ACDelco 18M1878 - Brake Master Cylinder - 0.937" Bore Cast Iron, 2 Mounting Holes
$6799
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ACDELCO part description
Gold™ Brake Master Cylinder
Product Attributes
| Brake Booster Included | No |
| Master Cylinder Cap Included | Yes |
| Master Cylinder Material | Iron |
| Port Quantity | 2 |
| Bleeder Hoses Included | Yes |
| Bore Diameter | 0.937 in. (23.7998 mm) |
| Master Cylinder Bore Size | 1.125 in. |
| Master Cylinder Bore Size | 1.125 in. |
| Mounting Hole Count | 2 |
| Mounting Hole Count | 2 |
| Notes | With Reservoir, Without Mounting Bracket |
| Notes | With Reservoir, Without Mounting Bracket |
| Primary Outlet Thread | 0.5 in. (12.7 mm) |
| Primary Outlet Thread | 0.5 in. (12.7 mm) |
| Programming Required | No |
| Programming Required | No |
| Pushrod Included | No |
| Pushrod Included | No |
| Secondary Outlet Thread | 0.5625 in. (14.2875 mm) |
| Secondary Outlet Thread | 0.5625 in. (14.2875 mm) |
| Style | With Rectangular Reservoir Cap |
| Style | With Rectangular Reservoir Cap |
| Primary Outlet Thread Diameter | 0.5 IN |
| Secondary Outlet Thread Diameter | 0.5625 IN |
| Weight (lb) | 1.4 lb |
| Master Cylinder Bore Diameter | 1.125 IN |
| Mounting Hole Quantity | 2 |
| Height (in) | 4.8 in |
| Width (in) | 5.8 in |
| Length (In) | 9.4 IN |
| Primary Outlet Thread Diameter | 12.7 MM |
| Secondary Outlet Thread Diameter | 14.287 MM |
| Master Cylinder Bore Diameter | 28.575 MM |
| Bore Size (in) | 1.125 in |
| Signs of Wear & Troubleshooting - Section 1 - Bullet 4 | A low or sinking brake pedal. |
| Product Description | ACDelco Professional Brake Master Cylinders use both aluminum and iron castings, making them a high quality replacement for many vehicles on the road today. These master cylinders contain both Ethylene Propylene (EPDM) and Styrene Butadiene (SBR) rubber components to provide superior resistance to heat, corrosion, and leakage. ACDelco Professional Brake Master Cylinders are ready to bench bleed and install right out of the box - no assembly required. These premium aftermarket replacement brake master cylinders are manufactured to meet your expectations for fit, form, and function. ⚠<b> WARNING:</b> Cancer and Reproductive Harm - www.P65Warnings.ca.gov |
| FAQ - Question 3 | Are these brake parts durable? |
| Signs of Wear & Troubleshooting - Section 1 - Header | Brake cylinder signs of wear include: |
| Signs of Wear & Troubleshooting - Section 1 - Bullet 1 | Brake warning light is on. |
| Good Maintenance Practices - Section 1 - Bullet 2 | Calipers and wheel cylinders should be checked every brake inspection and serviced or replaced as required. |
| Features & Benefits - Bullet 3 | Cast iron and aluminum specifications; no extra stress on the brake boosting mounting |
| Good Maintenance Practices - Section 1 - Bullet 1 | Check brake fluid level at every oil change. Replace fluid according to owner's manual recommendations. |
| Good Maintenance Practices - Section 1 - Bullet 4 | Check the thickness of your brake pads. |
| Signs of Wear & Troubleshooting - Section 1 - Bullet 3 | Difficulty stopping the vehicle. |
| FAQ - Question 1 | Do I have to replace all my brake parts when replacing my brake cylinder? |
| FAQ - Question 2 | Does ACDelco offer other grades of brake cylinders? |
| Signs of Wear & Troubleshooting - Section 1 - Bullet 2 | Fluid spots beneath the car, indicating there may be a leak within the cylinder. |
| Features & Benefits - Bullet 4 | Geometrical tolerance ensures that the body and plastic reservoir match for a proper fit |
| Good Maintenance Practices - Section 1 - Bullet 3 | Inspect the brake lines for rust, punctures, or visible leaks (You may be able to do this, but consult a qualified technician if necessary). |
| Good Maintenance Practices - Section 2 - Bullet 2 | Inspection of brake lining and pads for wear or contamination by brake fluid or grease. |
| Good Maintenance Practices - Section 2 - Bullet 1 | Inspection of the brake hoses for brittleness or cracking. |
| Good Maintenance Practices - Section 2 - Bullet 3 | Inspection of wheel bearings and grease seals. |
| Features & Benefits - Bullet 1 | Meets the brake performance requirements of SAE J1153 and J1154 testing, providing reliability and quality |
| Mounting Bracket Included | No |
| FAQ - Answer 1 | No, but it is a good idea to inspect them for wear-out, cracking, leaking etc. |
| Good Maintenance Practices - Section 2 - Bullet 4 | Parking brake adjustments (as needed). |
| Features & Benefits - Bullet 5 | Piston assembly and return spring help to prevent brake drag, which can cause premature brake pad wear |
| Features & Benefits - Bullet 2 | Pressure tested to ensure safe and confident braking |
| Good Maintenance Practices - Section 1 - Header | The following inspections and maintenance procedures can help prevent potential brake problems: |
| Good Maintenance Practices - Section 2 - Header | The following should be conducted by a qualified technician: |
| Reservoir Included | Yes |
| FAQ - Answer 2 | Yes, ACDelco also offers GM OE brake cylinders. |
| FAQ - Answer 3 | Yes, ACDelco Professional Brake Cylinders come with a 12 month / unlimited mile warranty. |
| Mounting Hole Diameter | 0.423 IN |
| Push Rod Included | No |
Additional Information
| Warranty Special | 24 Months/Unlimited Miles Limited Warranty (Parts Only). Please see ACDelco.com for more details|24 Months/40,000 Kilometers Limited Warranty (Parts Only). Please see ACDelcocanada.com for more details |
| Harmonized Tariff Code (HTS) | 8708305090 |
| Country of Origin (Primary) | CN |
| Country of Origin 3 | MX |
| Country of Origin 2 | TW |
| Warranty Special UOM | TX |
| UPC | 00707773315026 |
Fits Vehicles
- GMC G25/G2500 Van (1973)
- GMC K15/K1500 Pickup (1973-1974)
- GMC C15/C1500 Suburban (1973-1974)
- GMC C1500 (1979-1980)
- GMC G15/G1500 Van (1973-1974)
- GMC G1500 (1979-1980)
- GMC C15/C1500 Pickup (1973-1974)
- GMC C1500 Suburban (1979-1980)
- GMC P15/P1500 Van (1973-1974)
- GMC K15 (1975-1978)
- GMC K1500 (1979-1980)
- GMC K15 Suburban (1975-1978)
- GMC K15/K1500 Suburban (1973-1974)
- GMC G15 (1975-1978)
- GMC C15 Suburban (1975-1978)
- GMC C15 (1975-1978)
- Chevrolet G10 (1975-1980)
- Chevrolet P10 Van (1973-1974)
- Chevrolet K5 Blazer (1975-1980)
- Chevrolet K10 (1975-1980)
- Chevrolet C10 (1975-1980)
- Pontiac Grand Safari (1971-1978)
- Oldsmobile Cutlass Tiara (1976)
- Oldsmobile Cutlass Supreme (1969-1977)
- Oldsmobile Cutlass Salon (1975-1977)
- Oldsmobile F85 (1969-1972)
- Buick GS 455 (1970-1972)
- Buick GS (1970-1972)
- Buick GS 400 (1968-1969)
- Buick GS 350 (1968-1969)
- GMC Jimmy (1973-1980)
- Chevrolet C10 Suburban (1973-1980)
- Chevrolet Blazer (1973-1974)
- Chevrolet K10 Suburban (1973-1978)
- Chevrolet K10 Pickup (1973-1974)
- Chevrolet G20 Van (1973)
- Chevrolet G10 Van (1973-1974)
- Chevrolet C10 Pickup (1973-1974)
- Cadillac Seville (1976)
- Buick Apollo (1975)
- Buick Skyhawk (1975)
- Chevrolet Biscayne (1971-1972)
- Pontiac Executive (1970)
- Chevrolet El Camino (1971-1977)
- Oldsmobile Omega (1975-1979)
- Buick Special (1969)
- Oldsmobile 442 (1969-1971)
- American Motors Matador (1976-1978)
- Chevrolet Kingswood (1971-1972)
- Chevrolet Nova (1975-1979)
- Pontiac GTO (1971-1973)
- Cadillac Eldorado (1971-1975)
- Buick Sportwagon (1967-1972)
- Pontiac Tempest (1969-1970)
- Pontiac Ventura (1975-1977)
- Chevrolet Chevelle (1971-1973)
- Pontiac Phoenix (1977-1979)
- Chevrolet Townsman (1971-1972)
- Cadillac Calais (1971-1975)
- Pontiac Bonneville (1971-1980)
- Oldsmobile Vista Cruiser (1969-1975)
- Buick Riviera (1971-1978)
- Pontiac Laurentian (1974, 1976-1980)
- Pontiac Grandville (1971-1975)
- Chevrolet Caprice (1971-1980)
- Oldsmobile Toronado (1973, 1976-1978)
- Jeep J20 (1974-1980)
- Chevrolet Brookwood (1971-1972)
- Pontiac Grand Prix (1969-1977)
- Pontiac Grand LeMans (1975-1977)
- Buick Regal (1973-1977)
- GMC Sprint (1971-1977)
- Chevrolet Monte Carlo (1971-1977)
- Chevrolet Impala (1971-1980)
- Jeep J10 (1974-1980)
- Pontiac Grand Am (1973-1975)
- Buick Electra (1971-1980)
- Chevrolet Laguna (1973-1976)
- Chevrolet Malibu (1973-1977)
- Jeep Cherokee (1974-1980)
- Buick Centurion (1971-1973)
- Pontiac Parisienne (1971-1974, 1976-1980)
- Oldsmobile 98 (1971-1980)
- Cadillac Commercial Chassis (1971-1980)
- Chevrolet Bel Air (1971-1975)
- Buick Skylark (1967-1972, 1975-1979)
- Pontiac LeMans (1969-1977)
- Jeep Wagoneer (1974-1980)
- Buick LeSabre (1971-1980)
- Chevrolet Camaro (1970-1980)
- Buick Century (1973-1977)
- Pontiac Firebird (1970-1980)
- Buick Estate Wagon (1971-1980)
- Checker Marathon (1967-1979)
- Oldsmobile Custom Cruiser (1971-1980)
- Oldsmobile Cutlass (1969-1977)
- Cadillac DeVille (1971-1975, 1977-1980)
- Cadillac Fleetwood (1971-1980)
- Oldsmobile Delta 88 (1971-1980)
- Pontiac Catalina (1969, 1971-1980)
A true OEM auto parts brand for GM and non-GM vehicles, ACDelco® offers a wide portfolio of parts designed to keep vehicles on the road longer. These parts work precisely and fit perfectly because they are designed, engineered, tested, and backed by General Motors. But ACDelco also carries aftermarket components that go through the same 18-step quality approval process as the OE parts. Whether customers choose OE or aftermarket, they’d get the same reliable performance, precise engineering, and superior reliability for years to come. ACDelco’s expansive product portfolio includes alternators, filters, batteries, brakes, belts and hoses, oil and fluids, and suspension parts. These products are made to meet GM and non-GM vehicles’ ever-evolving powertrain, collision, maintenance, and repair needs.
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