Firestone Coil-Rite Rear Air Helper Spring Kit for Select Lexus & Toyota 1998-2021 (4135)

Fits select 1998-2021 Toyota 4Runner, 2007-2014 Toyota FJ Cruiser, and 2013-2018 Lexus LX570 (Base).

Improve your vehicle's ride quality and load-carrying capability with the Firestone Coil-Rite Rear Air Helper Spring Kit. These air springs are designed to be installed inside your vehicle's existing rear coil springs, creating a variable spring rate that addresses sag and instability under heavy loads. By adjusting the air pressure, you can level your vehicle to maintain proper headlight aim, improve steering geometry, and enhance braking effectiveness, whether you are hauling gear or towing a trailer.

Constructed from durable, elastic polyurethane, these Coil-Rite inserts are built to withstand the rigors of both on-road and off-road environments. They function as a cushion to prevent bottoming out and reduce tire wear by maintaining an even distribution of weight across all four wheels.

• Provides 500–1,000 lbs of load-leveling capacity per set (do not exceed GVWR)
• Made from high-strength, elastic polyurethane for long-term durability
• Operating temperature range: -40°F (-40°C) to 180°F (82°C)
• Adjustable air pressure allows for fine-tuning based on specific load requirements
• Helps maintain vehicle stability and reduces suspension fatigue
• Manufacturer Part Number: 4135