A suspension system that includes a simplified lockout mechanism and an adjustable blow-off mechanism. The system includes a valve mechanism and a valve actuating assembly, a valve mechanism housing and a resilient member disposed between the valve mechanism and the valve mechanism housing. The valve mechanism is slidably mounted along the valve mechanism housing and it separates a first chamber from a second chamber. The valve actuating assembly operates the valve mechanism between open and closed positions. The resilient member is configured to be deformable by the valve mechanism as the valve mechanism is slidably displaced by an increasing pressure in the first fluid chamber. The sliding valve mechanism is configured to collide against the valve actuating assembly when a blow-off pressure is reached in the first fluid chamber switching the valve mechanism from the closed position to the open position.