Rear Spring 5in ID 20in Tall

The Rear Spring 5in ID 20in Tall (model 18SNT-080) from HYPERCO is a precision coil spring engineered for serious suspension builds and performance vehicle modifications. Built for mechanics and enthusiasts who demand repeatable, predictable suspension geometry, this rear spring delivers the consistent spring rate that separates engineered setups from off-the-shelf compromises. Whether you're tuning a track car, restoring a classic with modern handling, or dialing in a lifted truck platform, this spring provides the foundation for controlled articulation and load support.

This conventional coil spring features an 80 lb/in spring rate with a 5-inch inner diameter and 20-inch overall length, machined from high-quality steel and finished in blue powder coat for corrosion resistance and durability in harsh driving conditions. The 80 lb/in rate is mid-range stiffness—firm enough to handle increased payload and aggressive cornering without excessive harshness over bumps, yet compliant enough for street-driven vehicles. The compact 5-inch ID allows integration into space-constrained rear suspension designs, while the 20-inch height accommodates OEM and custom mounting points on a wide variety of platforms. HYPERCO's manufacturing tolerances ensure spring rate consistency across production runs, critical for matched-pair setups where suspension balance directly affects handling and tire wear.

This rear spring suits builders upgrading factory suspension on trucks, SUVs, and performance sedans, as well as racers fine-tuning loaded weight distribution. Installation requires proper coil spring compressors and should verify OEM spring pocket geometry and load limits before fitment. The blue powder-coated finish resists UV degradation and road salt, extending service life in both street and off-road environments. Pair with matched front springs and quality dampers to achieve balanced ride height, predictable body roll, and optimal tire contact patch across varying driving conditions.