Firestone 4155 Coil-Rite Air Helper Spring Kit Rear fits Toyota 04-17 Sienna

The Firestone Coil-Rite Air Helper Spring Kit Rear is a performance upgrade designed for vehicles with coil spring suspensions. It features air helper springs that fit inside existing coil springs to provide a variable spring rate, helping to level the vehicle and improve braking and handling under heavy loads or challenging road conditions. Constructed from durable, elastic polyurethane, these springs support 500-1000 lbs per set (not exceeding the vehicle's GVWR) and are engineered to operate effectively within temperatures ranging from -40°F to 180°F. The Coil-Rite system allows precise control of air pressure, enabling drivers to adjust spring performance easily, similar to inflating a tire, for enhanced ride comfort and stability.

This kit is suitable for rear suspension applications on 2004-2017 Toyota Sienna models. It is designed to be a direct-fit, bolt-on upgrade that enhances load-carrying capacity and ride quality, especially when towing or carrying heavy loads. The installation involves fitting the air helper springs inside the existing coil springs, providing an adjustable solution for varying load conditions. The kit includes all necessary components for a straightforward installation, making it ideal for daily drivers, towing, and vehicles frequently subjected to heavy loads or uneven terrain.