Eibach Progressive Tender Springs - Coilover Helper Spring

Eibach Progressive Tender Springs are precision-engineered secondary springs designed to work in tandem with a main coilover spring, creating a sophisticated dual-spring suspension system. Unlike a basic helper spring, the Tender Spring carries a specific progressive spring rate that actively shapes the initial suspension response — delivering a softer initial rate when both springs compress together, then seamlessly transitioning to the firmer final rate of the main spring once the tender spring fully closes.

How the Dual-Spring System Works:

• Tender spring determines the initial rate of the spring system; the main spring determines the final rate
• Progressive rate design increases resistance as compression increases for a smooth, seamless rate transition
• Keeps the main spring properly seated on the perch throughout full suspension travel, including droop and full extension
• Eliminates spring separation, clunking, rattling, and inconsistent damper performance caused by a loose main spring
• Maintains proper damper shaft alignment and consistent valving behavior under all conditions

Eibach Quality & Engineering:

• Manufactured from premium Hi-Ten spring steel using state-of-the-art cold-winding processes
• Shot-peened surface treatment for enhanced fatigue resistance and long-term dynamic durability
• Corrosion protection through phosphating and epoxy coating for lasting reliability in all environments
• Precision tolerances ensure exceptional repeatability — critical for consistent and repeatable suspension tuning
• Each spring is imprinted with part number, spring rate, and physical dimensions for easy identification in the field
• Manufactured to EN ISO 9001 and QS9000 certified quality standards

Part of the Eibach ERS Race Spring System:

Eibach's world-renowned ERS (Eibach Race Spring) system is the most comprehensive and widely used race spring platform in motorsport, developed through competition at the highest levels — including Formula 1, NASCAR, WRC, and IndyCar. By mixing and matching Eibach Main, Tender, and Helper springs from their extensive lineup, suspension engineers and performance enthusiasts can dial in the exact spring rate combination for any application, from dedicated race builds to high-performance street cars.

Eibach Progressive Tender Springs are available in a wide range of rates and sizes to suit virtually any coilover platform, making them the ideal choice wherever precise spring rate tuning, noise elimination, and consistent damper performance are required.