4" ReadyLIFT Suspension BIG Lift Kit (Ford Super Duty 2017-2022)

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ITEM# RLF237

MFG# 49-27421

• Fits 2017-2022 Ford Super Duty Power Stroke 4WD✔
• 4" Coil Spring Lift Kit With (4) Monotube Falcon 1.1 Shocks.✔
• Eye-catching HD Tubular Radius Arms helps to correct caster angle.✔
• Bolt-on lift kit - no structural modifications required.✔
• Allows for up to 37" tall tires on 9" wide wheels with +18 offset.✔
• Diesel trucks with rear single-wheel only.✔
• Note: Tremor versions will NOT gain the full 4 inches over stock ride height. NOT recommended for 2WD or gas trucks. 2017-2019 ride height may be slightly lower. Single Cab configuration has NOT been validated for fitment & drivability by ReadyLIFT. ✔

ReadyLIFT Suspension is now offering ReadyLIFT's first 4" Coil Spring Lift Kit fitting 2017-2022 Ford Super Duty F250/F350 4WD Power Stroke® trucks with new Tubular Radius Arms. The 49-27421 includes front and rear Falcon 1.1 Monotube series performance shocks with ReadyLIFT's venerable front track bar relocation bracket, tubular radius arms, and rear fabricated blocks. This delivers an excellent alternative for lifting a F250/F350 Super Duty trucks to fit larger tires. The coil spring system allows for increased tire sizes and widths along with providing improved ground clearance on a head-turning stance! Many consider this lift height the 'sweet spot' for Super Duty driving dynamics and maximum tire size while maintaining everyday practicality.

The all-new Radius Arms are designed to correct the suspension geometry on lifted models. These new radius arms are heavy duty and are built to handle the use and abuse demanded out of Super Duty trucks. The new radius arms hold up to the abuse and surpass the factory radius arms and support gussets. The arms are formed inward, allowing for additional tire clearance, and providing the ability to install oversized tires. The direct bolt-on design promotes quick and easy installation. This optimum lift height allows for up to 37" tall tires. The coil spring kit delivers a great ride and handling performance! The key ingredients to improving your ride are the new specially engineered coil springs teamed with Falcon shocks and track bar relocation! This combination is more than just a lift kit, this is a performance and ride-enhancing kit that will really delight consumers with how well it rides and performs both on and off-road.

The ReadyLIFT 4" Coil Spring lift kit system for 2017-2022 Ford Super Duty trucks also includes model-specific brake line extension brackets, ReadyLIFT's time-tested bump-stop extension brackets, and new front sway bar frame mount extension brackets to keep the factory sway bar in the proper position. If you want tough looks and a smooth but controlled ride, then you want the new Super Duty 4" Coil Spring Suspension Kit System.

37x12.50 for no rub on a 9" wide wheel with 0 offset

18" - 37X12.5R18

20" - 37X12.5R20

22" - 325/60R22

Tire Size Note: ReadyLIFT wheel and tire fitment recommendations are typically based on Wheel Pros wheels and Nitto tires. Due to product differences among tire manufacturers, tire specifications and dimensions including, but limited to, overall diameter, rolling diameter, tread width, aspect ratio, lug pattern, sidewall construction and inflation pressure, will vary meaningfully by tire and wheel manufacturer. Every tire and wheel combination should be test fit prior to installation. Consult your local installer to learn more about the right tire fitment for your application.

Ride Quality Note: When lifting a vehicle and installing aftermarket wheels and tires, a tire manufacturer's construction and material quality can alter vehicle ride quality. When increasing a vehicle wheel and tire size, most larger aftermarket truck and SUV tires are 10-ply (or more) E tires compared to typical OEM 6-ply C tires. This more rigid sidewall construction increases the perception of suspension stiffness often described as ride harshness. The ride, handling, traction, noise, fuel economy, and wear differences between All-Season, All-Terrain, Mud-Terrain, or Trail-Terrain type tires can be significant. Please take into account tire and wheel choice will generally have a meaningful impact on the ride & handling experience.

Please read Instructions thoroughly and completely before beginning installation. Installation by a certified mechanic is recommended.

Estimated Installation Time: 4.5 Hours +/- 0.5 hours (excluding alignment and wheel/tire assembly)

View Instruction Sheet

· 4" Lift Springs
· Falcon 1.1 Monotube Front and Rear Shocks
· Track Bar Relocation Bracket
· Radius Arm
· Sway Bar Drops
· Bump Stop Extensions
· Carrier Bearing Drop
· Front Brake Line Brackets
· Fabricated Rear Lift Blocks
· Hardware Pack

Local pickup welcome.

Some vehicles may require additional modifications or parts.

Guaranteed Fitment.

Questions Call us at (888) 814-1158