AIR BRAKES - GENERAL INFORMATION4x2 Tractor (Figure 10)Primary service system is at the rear axle brakes.Secondary service system is at the front axle brakes.Thetrailer service brakes will assist either the primary or thesecondary systems during trailer applications.Figure 10 - 4x2 Tractor With Refined Split Air System and Modular Control Valve For Spring Brakeand TractorProtection ControlsCTS-4154Y - Page 10
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business