228AM3
Spring Nut
Mack

A Spring Nut delivers fast, vibration-tolerant fastening for rugged Mack truck assemblies. This captive nut uses a spring-loaded feature to stay in place during panel installation, preventing dropped or misaligned fasteners in crowded engine bays, cab interiors, and chassis sections. Constructed from durable steel with a protective finish, it resists corrosion and abrasion while maintaining consistent clamping force as the vehicle flexes under load and during long highway runs. The spring mechanism helps keeper alignment when multiple fasteners are used, reducing the risk of cross-threading and the need for rework caused by loose hardware. Typical benefits include quicker assembly, fewer interruptions for repositioning parts, and enhanced reliability in high-vibration environments. When ordering, ensure the thread size matches your bolts and that the boss or mounting hole dimensions suit the chassis design. Proper installation is straightforward: drop the nut into its recess, compress the spring to seat, thread in your bolt, and torque to specification. Source One Parts Center emphasizes stocking this type of fastener for efficient field service, noting it supports consistent maintenance outcomes across Mack applications.