TUBE, HEIGHT CONTROL, NO.4

Height Control Hydraulic Tube (Rear Suspension Line)

This replacement hydraulic line is required on vehicles equipped with automatic height/level control suspension. It carries pressurized fluid between the height control valve/actuator and the suspension unit, helping the system raise or lower the body smoothly under load. When towing, carrying passengers, or driving on uneven roads, this tube helps keep ride height correct and stable .

How It Works

The tube acts like a high-pressure pathway. As the control valve commands adjustment, hydraulic fluid flows through the line to extend or retract the suspension components. Proper sealing and internal cleanliness are critical so pressure is transmitted instantly without delay, vibration, or restriction.

Why This Part Matters

A healthy height control line supports safe handling, even tire contact, and consistent headlight aim. It also prevents the pump from overworking, which protects other expensive suspension parts.

Symptoms of a Failed Tube

If the tube is cracked, corroded, kinked, or leaking, you may notice sagging on one side, slow height changes, harsh ride, or warning lights. Fluid loss can cause the pump to run loudly and may lead to complete leveling failure. Continued driving with a leak can damage the pump and valves, and may reduce braking stability due to poor weight balance ⚠️.