Dorman W78745 Wheel Cylinder 1971-1989 GMC B6000 - view 1
Dorman W78745 Wheel Cylinder 1971-1989 GMC B6000 - view 2
Dorman W78745 Wheel Cylinder 1971-1989 GMC B6000 - view 3
Dorman W78745 Wheel Cylinder 1971-1989 GMC B6000 - view 4
Dorman W78745 Wheel Cylinder 1971-1989 GMC B6000 - view 1
Dorman W78745 Wheel Cylinder 1971-1989 GMC B6000 - view 2
Dorman W78745 Wheel Cylinder 1971-1989 GMC B6000 - view 3
Dorman W78745 Wheel Cylinder 1971-1989 GMC B6000 - view 4
Dorman Products

Dorman W78745 Rear Right Upper Lower Drum Brake Wheel Cylinder 71-89 Chevy P30

In stock
SKU: 591|W78745
Confirm Fitment Before You Buy
Not sure it fits? Message Year/Make/Model/Engine (2WD/4WD if applicable) and we’ll help confirm compatibility.
Why buy from Koskowski Automotive?
• 50+ years (since 1972) • Dorman Authorized Seller • Fast shipping • Easy returns
$38.02
Select your vehicle at the top of the page to check fitment.
Vehicle Fitment: Use the table below to match your exact configuration. If you don’t see your exact setup, message us before ordering.

Product details

  • SKU 591|W78745
  • Barcode 082702414149

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Description

This direct replacement drum brake wheel cylinder was specifically engineered to match the fit, function and performance of the original wheel cylinder on particular vehicles. It is manufactured and tested for quality assurance.

  • Ideal replacement - specifically engineered to be direct match for original drum brake wheel cylinder on particular vehicles
  • Cost-effective fix - replacement of cylinder while servicing drum brakes is fastest, surest way to ensure brake performance
  • Quality materials - made with high-quality EPDM rubber cups and boots for long-lasting performance
  • Professionally tested - wheel cylinder bores are surface-tested to ensure an optimum sealing surface for the pressure cups

Vehicle Fitment

Year Make Model Position Notes
1986-1989 Chevrolet B60 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1986-1989 Chevrolet B60 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1985 Chevrolet B60 Rear Right Lower Bore: 1.50 In.
1985 Chevrolet B60 Rear Right Upper Bore: 1.50 In.
1983-1984 Chevrolet B60 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.125 In.
1983-1984 Chevrolet B60 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.125 In.
1982 Chevrolet B60 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1982 Chevrolet B60 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1971-1972 Chevrolet C30 Pickup Rear Right 11,000 Lb. Axle; Bore: 1.50 In.
1987-1989 Chevrolet C50 Rear Right Lower Bore: 1.50 In.
1987-1989 Chevrolet C50 Rear Right Upper Bore: 1.50 In.
1983 Chevrolet C50 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1983 Chevrolet C50 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1980 Chevrolet C50 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1980 Chevrolet C50 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1977 Chevrolet C50 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1977 Chevrolet C50 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1986-1988 Chevrolet C60 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1986-1988 Chevrolet C60 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1985 Chevrolet C60 Rear Right Lower Bore: 1.50 In.
1985 Chevrolet C60 Rear Right Upper Bore: 1.50 In.
1983-1984 Chevrolet C60 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.125 In.
1983-1984 Chevrolet C60 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.125 In.
1982 Chevrolet C60 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1982 Chevrolet C60 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1981 Chevrolet C60 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1981 Chevrolet C60 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1977 Chevrolet C60 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1977 Chevrolet C60 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1982-1983 Chevrolet C70 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1982-1983 Chevrolet C70 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1983 Chevrolet P30 Rear Right 12,000 to 14,000 Lb. GVW; Bore: 1.50 In.; wo/Motorhome Chassis
1983 Chevrolet P30 Rear Right 14,000 Lb. GVW; Bore: 1.50 In.; w/Motorhome Chassis
1975-1977 Chevrolet P30 Rear Right 12,000 to 14,000 Lb. GVW; Bore: 1.50 In.; wo/Motorhome Chassis
1975-1977 Chevrolet P30 Rear Right 14,000 Lb. GVW; Bore: 1.50 In.; w/Motorhome Chassis
1974 Chevrolet P30 Van Rear Right 12,000 to 14,000 Lb. GVW; Bore: 1.50 In.; wo/Motorhome Chassis
1973-1974 Chevrolet P30 Van Rear Right 14,000 Lb. GVW; Bore: 1.50 In.; w/Motorhome Chassis
1973 Chevrolet P30 Van Rear Right 11,000 Lb. Axle; Bore: 1.50 In.; wo/Motorhome Chassis
1972 Chevrolet P30 Van Rear Right 11,000 Lb. Axle; Bore: 1.50 In.
1983-1987 Chevrolet P40 Rear Right Lower 15 In. Brakes; Bore: 1.50 In.
1983-1987 Chevrolet P40 Rear Right Upper 15 In. Brakes; Bore: 1.50 In.
1986-1989 GMC B6000 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1986-1989 GMC B6000 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1985 GMC B6000 Rear Right Lower Bore: 1.50 In.
1985 GMC B6000 Rear Right Upper Bore: 1.50 In.
1983-1984 GMC B6000 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.125 In.
1983-1984 GMC B6000 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.125 In.
1982 GMC B6000 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1982 GMC B6000 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1980 GMC B6000 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1980 GMC B6000 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1971-1972 GMC C35/C3500 Pickup Rear Right 11,000 Lb. Axle; Bore: 1.50 In.
1988-1989 GMC C5000 Rear Right Lower Bore: 1.50 In.
1988-1989 GMC C5000 Rear Right Upper Bore: 1.50 In.
1985 GMC C5000 Rear Right Lower Bore: 1.50 In.
1985 GMC C5000 Rear Right Upper Bore: 1.50 In.
1982 GMC C5000 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1982 GMC C5000 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1981 GMC C5000 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1981 GMC C5000 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1988 GMC C6000 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1988 GMC C6000 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1986 GMC C6000 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1986 GMC C6000 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1985 GMC C6000 Rear Right Lower Bore: 1.50 In.
1985 GMC C6000 Rear Right Upper Bore: 1.50 In.
1983-1984 GMC C6000 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.125 In.
1983-1984 GMC C6000 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.125 In.
1982 GMC C6000 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1982 GMC C6000 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1982 GMC C7000 Rear Right Lower 15 In. x 5 In. Brakes; Bore: 1.50 In.
1982 GMC C7000 Rear Right Upper 15 In. x 5 In. Brakes; Bore: 1.50 In.
1980 GMC C7000 Rear Right Lower 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1980 GMC C7000 Rear Right Upper 15 In. x 4 In. Brakes; 15 In. x 5 In. Brakes; Bore: 1.50 In.
1971-1972 GMC P25/P2500 Van Rear Right 11,000 Lb. Axle; Bore: 1.50 In.
1975-1976 GMC P35 Rear Right 12,000 to 14,000 Lb. GVW; Bore: 1.50 In.; wo/Motorhome Chassis
1975-1976 GMC P35 Rear Right 14,000 Lb. GVW; Bore: 1.50 In.; w/Motorhome Chassis
1974 GMC P35/P3500 Van Rear Right 12,000 to 14,000 Lb. GVW; Bore: 1.50 In.; wo/Motorhome Chassis
1973-1974 GMC P35/P3500 Van Rear Right 14,000 Lb. GVW; Bore: 1.50 In.; w/Motorhome Chassis
1973 GMC P35/P3500 Van Rear Right 11,000 Lb. Axle; Bore: 1.50 In.; wo/Motorhome Chassis
1972 GMC P35/P3500 Van Rear Right 11,000 Lb. Axle; Bore: 1.50 In.
1984-1987 GMC P4500 Rear Right Lower 15 In. Brakes; Bore: 1.50 In.
1984-1987 GMC P4500 Rear Right Upper 15 In. Brakes; Bore: 1.50 In.

Please confirm the part number and your vehicle's year, make, model and engine before ordering. Questions? Message us with your VIN and we'll check fitment for you.

Specifications

Brand Dorman
Part Number W78745
UPC 082702414149
Placement Rear, Right, Upper, Lower
Material Cast Iron
Air Vent (Bleeder Valve) Yes
Brake Component Inlet Thread Size 7/16-24
Inside Diameter 1.5 in
Package Contents 1 Drum Brake Wheel Cylinder
Thread Diameter 7/16 in.
Country of Origin China
Warranty Limited Lifetime

OE & Interchange Numbers

2620633 General Motors (OE)
5472485 General Motors (OE)
5472821 General Motors (OE)
WC250120 Interchange
W-86012 Interchange
F78745 Interchange
78745 Interchange
101-1636 Interchange
18E83 Interchange
84-44012 Interchange
W906337 Interchange
33656 Interchange
WC37241 Interchange
WC78745 Interchange
375-47065 Interchange
135.66012 Interchange
134.66012 Interchange