Long Box 13513 for 4-SPR External Mount

This 13513 LONG BOX for 4-SPR external mount is a critical component in heavy-duty suspension assemblies, engineered for trucks that use an external mount style with a four-spring configuration. The long-box design accommodates extended spring stacks or extra travel while ensuring the box remains securely mounted to the chassis. Made to exacting tolerances, it delivers consistent alignment, rugged durability and minimal maintenance downtime. When you source this component from Wofford Truck Parts, you gain access to a premium quality unit built for demanding commercial use — whether hauling heavy loads, operating in harsh environments or requiring high-cycle reliability. Install this 13513 unit in your rig and you’ll benefit from a precise fit, reinforced structural design, and the assurance of sourcing from a trusted heavy-duty parts provider.