Firestone 6125 Coil-Rite Replacement Air Spring 4 x 11 Service Part

The Firestone 6125 Coil-Rite Replacement Air Spring is a direct-fit service replacement bellow measuring 4 x 11 inches, designed for use with Firestone Coil-Rite air helper spring kits. Engineered from durable, elastic polyurethane, this replacement air spring restores the load-leveling and ride-improvement performance of your existing Coil-Rite system without requiring a full kit replacement.

Key Features:

• Fits inside existing coil springs to produce a variable spring rate — softer when unloaded, firmer under load
• Supports 500–1,000 lbs. per set (not to exceed vehicle GVWR)
• Adjustable air pressure from 5 to 35 PSI for fine-tuning to load and road conditions
• Helps level vehicle stance, improve braking and handling, reduce tire wear, and maintain proper headlight aim
• Constructed from durable elastic polyurethane for long-term durability and consistent performance
• Rated for operation in temperatures from -40°F (-40°C) to 180°F (82°C)
• No drilling required for installation

Firestone Coil-Rite air springs are the trusted choice for vehicles with coil spring suspensions that haul heavy loads or tow trailers. Adjusting air pressure is as simple as inflating a tire, allowing on-the-fly tuning for varying cargo and road conditions. This 6125 service part ensures your Coil-Rite system continues performing at its best.