Air Springs & Level Valves for the Kenworth T300-T450 Model. Keep your Kenworth's suspension system in top shape with high-quality, aftermarket air springs and leveling valves. Find rolling lobe air bags, adjustable linkage kits, and replacement adapters for AG100, AG200, AG380, AG400L, and more. Upgrade, repair, or maintain your air ride system for a smoother, more stable ride on any terrain. Durable, compatible, and affordable'perfect for heavy hauls or rough roads!