Description

Overview

The spring brake modulating valve SR7 is designed to control spring brake actuators in heavy trailer and tractor applications, providing controlled parking and emergency braking through the spring brake section of the chambers. This spring brake modulating valve SR7 helps maintain braking control if a service circuit fails, while still delivering reliable park brake function. As a result, it suits modern dual circuit air brake systems where safe, progressive spring brake application is required.

Features

This valve is built for use in two tank, three valve trailer systems and compatible tractor layouts, so it integrates easily into common heavy vehicle air brake designs. It is corrosion and rust proof which helps maintain long term performance in harsh on road conditions. Additionally, the spring brake modulating valve SR7 offers controlled modulation of the spring brakes during a primary circuit failure, instead of a sudden full spring application. In addition, it supports stable park brake application when the parking control is used.

Specifications and Materials

The SR7 design is intended for use with standard air brake system pressures in heavy commercial vehicles, and it works with dedicated spring brake chambers and service relay valves in the same circuit. The valve controls air flow to and from the spring brake sections to provide both modulated emergency braking and full park brake hold when required. Supply and delivery ports are configured for typical trailer plumbing layouts, so installations can follow standard air brake routing with appropriate fittings and adaptors as specified by the system designer. Part number: AB8463. For a detailed explanation of spring brake modulating valve operation, see this manufacturer technical guide

Compatibility and Fitment

This cross-reference listing means this valve is a suitable replacement for the part numbers and applications shown. Some changes in air line plumbing may be required. 5010390, 801329, K021558, T5010390, SR-7

Compliance and Safety

The spring brake modulating valve SR7 is intended to be installed and tested by qualified technicians familiar with heavy vehicle air brake systems. Correct plumbing, mounting, and leak checking are critical to ensure both service and park brake functions operate as designed. Furthermore, the system must be drained, isolated, and secured before any work begins to avoid injury from stored air pressure. After installation, technicians should confirm proper modulation of the spring brakes during service circuit failure simulations and check that park brake applications and releases are consistent on all axles.

Trailer Applications

This valve suits heavy trailer and prime mover trailer combinations using two tank, three valve systems where spring brake chambers provide both parking and emergency braking functions. It is typically mounted near the trailer axles or in a protected chassis position to shorten delivery line lengths and improve response times. Moreover, it is appropriate for general freight, tanker, and other on highway trailer applications that use spring brakes for parking and emergency control. When replacing an existing SR7 pattern valve, installers should match porting, mounting orientation, and control line routing to the original layout wherever possible.

Cross-reference and Suitability

This part cross-references to or suits the following equivalent part numbers and compatible alternatives:

These cross references help confirm interchange in fleets where different supplier numbers have been used over time, however technicians should still verify port configuration and mounting against the original unit before final installation.

Why Choose ICS Trailers

ICS Trailers focuses on practical, workshop ready air brake parts that suit Australian heavy vehicle conditions and fleet requirements. Every item is selected to support dependable braking performance and straightforward service procedures. In addition, our team can help match valves to your existing system layout so you can minimise downtime and rework. Browse more options in our Air Brake Parts category at ICS Trailers