Product Description
The 379474 Hydrovac is a Third Series single-piston vacuum/hydraulic power brake booster designed for older commercial trucks, buses, trailers, and other vehicles equipped with hydraulic brakes and engine vacuum assist.
The unit uses engine vacuum to increase hydraulic braking pressure beyond what the driver could produce through the master cylinder alone. The 379474 measures approximately 6-3/4 inches in diameter and 14-1/2 inches overall. It uses a 1/2-inch hydraulic input, 1/2-inch hydraulic output, 1/2-inch air-cleaner connection, and 3/8-inch vacuum supply connection.
The 379474 is commonly associated with the 374000 / 374000X replacement family. Cross-reference catalogs also associate it with RV379474X, PB-374000-R, Cardone 51-8028, and 2208488.
Part Number: 379474
Product Type: Hydrovac Vacuum/Hydraulic Brake Booster
Series: Third Series
Design: Single Piston
Diameter: 6-3/4 in.
Overall Length: 14-1/2 in.
Hydraulic Input: 1/2"
Hydraulic Output: 1/2"
Air Cleaner Connection: 1/2"
Vacuum Supply: 3/8"
Cross References: 374000, 374000X, RV379474X, PB-374000-R, 51-8028, 2208488
