Bleeding the ABS brakes on a 1995 Suburban 4×4 requires a specific procedure due to the Kelsey-Hayes EBC310 ABS system. This system, used in GM trucks from 1995 to the early 2000s, features three sections: one for each front wheel and one for the rear axle. Each section has an Isolation valve and a Dump-Valve/Low-Pressure Accumulator.
The challenge lies in bleeding the low-pressure accumulator, which is positioned behind the dump-valve and inaccessible for traditional bleeding methods. Effectively flushing fluid and air from this component necessitates cycling the ABS. The factory-approved method involves using a GM Tech 1 Scan Tool to command the ABS cycling process. This scan tool allows for precise control and ensures complete fluid exchange within the system.
However, an alternative method exists for those without access to a scan tool. This involves driving the vehicle on a gravel or snow-covered road and forcefully applying the brakes to induce wheel lockup and trigger the ABS cycle. While this method can cycle the ABS, it carries inherent risks.
Firstly, the brakes must be functional enough for safe operation on a loose surface. Secondly, cycling the ABS in this manner can release trapped air from the accumulators into the brake lines, potentially compromising braking performance. Even if successful in activating all three circuits (left front, right front, and one rear wheel), further bleeding is necessary to remove any remaining air in the system after this procedure.
This “shade-tree” method should be approached with caution, understanding the potential dangers. The recommended approach remains using the 1995 Suburban 4×4 ABS brake bleeding scan tool (GM Tech 1) for a controlled and effective bleed. This ensures complete fluid replacement and minimizes the risk of introducing air into the brake lines. Proper ABS bleeding is crucial for optimal braking performance and safety.
