Here's a breakdown of the potential adjustments and how they're made:
1. Ride Height: This is typically adjusted via the height control system. This system usually consists of:
* Height control valves: These valves regulate the air pressure in the air springs based on signals from the height sensors. Adjustment is typically *not* done directly on these valves unless you're a trained technician dealing with a malfunctioning valve.
* Height sensors: These sensors monitor the ride height and send signals to the height control valves. These are usually located near the axles. They don't require direct adjustment unless faulty and should be replaced if malfunctioning.
* Air compressor: This maintains the air pressure in the system. Again, you wouldn't directly adjust this unless it's underperforming (low air pressure).
* ECU (Electronic Control Unit): The ECU manages the entire system, receiving inputs from sensors and controlling the valves. You shouldn't attempt to adjust anything directly on the ECU.
If you need to adjust the ride height, the problem likely lies within a faulty component within these systems (sensor, valve, compressor). You'll need to:
* Diagnose the problem: Use a diagnostic tool (Freightliner's diagnostic software is usually required) to identify any fault codes related to the air suspension system.
* Repair or replace the faulty component: This requires specialized knowledge and tools. Replacing a height sensor or air valve is a job best left to a qualified mechanic.
2. Air Spring Pressure (indirectly through ride height): You don't directly adjust the pressure in the air springs. The height control system manages this. If the ride height is incorrect, this points to a problem within the system itself, not needing direct air spring manipulation.
3. Shock Absorber Dampening (if equipped with air shocks): Some air ride systems might incorporate air shocks. These typically don't have user-adjustable dampening. Their functionality is tied to the system's overall air pressure management.
In summary: Unless you're a trained heavy-duty truck mechanic with experience in air suspension systems, you should not attempt to adjust the air ride suspension on your Freightliner Century yourself. Attempting to do so without the proper knowledge and tools could lead to damage to the vehicle, injury, and potentially costly repairs. Take it to a qualified heavy-duty truck repair shop or Freightliner dealer for diagnosis and repair. They have the diagnostic tools and expertise to identify and fix the issue correctly.
