Firestone 4186 Coil-Rite Rear Air Helper Springs Kit for 08-14 GM SUV Autoride

Vehicle Fitment

• 2008-2014 Cadillac Escalade (Base, Platinum, Luxury, Premium) 2WD/4WD (Autoride)
• 2008-2014 Cadillac Escalade ESV (Base, Platinum, Luxury, Premium) 2WD/4WD (Autoride)
• 2008-2013 Cadillac Escalade EXT (Base, Luxury, Premium) 2WD/4WD (Autoride)
• 2011-2013 Chevrolet Avalanche 1500 2WD/4WD (Autoride)
• 2008-2014 Chevrolet Suburban 1500 2WD/4WD (Autoride)
• 2008-2014 Chevrolet Tahoe 2WD/4WD (Autoride)
• 2008-2014 GMC Yukon 2WD/4WD (Autoride)
• 2008-2014 GMC Yukon XL 1500 2WD/4WD (Autoride)

Features

• Coil-Rite air helper springs add adjustable support to rear coil suspension
• Designed to work with autoride suspension for level ride under load
• Durable polyurethane construction resists harsh conditions
• Easy manual adjustment of air pressure for varying cargo/tow loads
• Helps reduce rear squat and improves ride comfort under load
• Improves vehicle stability, braking, and handling
• No drilling required on most applications
• Operates reliably in temperature extremes

Specifications

• Part Number: 4186 (W237604186)
• Application: Rear axle - coil spring suspension
• Air Spring Diameter: ~4.0 inches
• Air Spring Length: ~9.0 inches
• Capacity: ~1,000 lbs per set (varies with vehicle GVWR)
• Pressure Range: ~5-25 PSI (typical adjustable range)
• Material: Elastic polyurethane with steel support hardware
• Average install time: ~1-2 hours

Included Components

• 2x Rear air helper springs
• 2x Support plates
• Air line kit
• 2x Manual inflation valves
• Mounting hardware (brackets, bolts)

Product Description

The Firestone 4186 Coil-Rite Rear Air Helper Springs Kit is engineered for GM SUVs equipped with rear coil spring suspension and autoride systems, offering adjustable load support and improved ride quality when carrying cargo or towing. These air helper springs fit inside your existing coils and create a variable rate spring that helps keep the vehicle level under load while enhancing stability, handling, and braking performance. The durable polyurethane construction is built to withstand a wide range of temperatures and road conditions.

Adjusting the air pressure in the helper springs is simple and allows drivers to fine-tune their suspension to match load weight, reducing rear squat and improving comfort. Installation is straightforward on most models and averages around one to two hours with no drilling required. Ideal for owners of 2008-2014 Cadillac Escalade and Escalade ESV, 2008-2013 Escalade EXT and Avalanche 1500, 2008-2014 Chevrolet Suburban and Tahoe, and 2008-2014 GMC Yukon and Yukon XL 1500 who want better rear load control and ride quality.