Prothane 4-1704 Front Lower Coil Spring Isolator Kit

The Prothane 4-1704 is a front lower coil spring isolator kit designed as a direct replacement for worn or deteriorated factory rubber isolators. Manufactured from Prothane's proprietary red polyurethane compound, these isolators deliver significantly greater durability and resistance to compression set, oil, and road chemicals compared to OEM rubber units.

Coil spring isolators serve as the cushioning interface between the coil spring and the spring seat, dampening noise, vibration, and harshness (NVH) transmitted through the suspension. As factory rubber isolators age, they crack, compress, and lose their shape — leading to clunking noises, uneven spring seating, and degraded ride quality. Prothane's polyurethane formulation restores proper spring isolation while providing a firmer, more responsive chassis feel.

Key Features:

• Made from Prothane's proprietary polyurethane compound for extended service life
• Direct OEM replacement — no modifications required for installation
• Resistant to compression set, oils, solvents, and road chemicals
• Reduces suspension noise, vibration, and harshness (NVH)
• Restores proper coil spring seating and alignment
• Includes grease for installation
• Manufactured in the USA

Prothane polyurethane suspension components are a trusted upgrade for drivers seeking improved suspension longevity and chassis feedback over stock rubber components.