Skyjacker JKU40FDR 4in Dual Rate Front Coil Springs 07-18 Wrangler JK Unlimited

Vehicle Fitment

• 2007-2018 Jeep Wrangler JK Unlimited - Sport, Sahara, Rubicon (4-Door, 4WD) - Front, 4 inch lift

Fitment Notes

• Front position only - designed for 4 inches of front lift
• 4-Door Wrangler JK Unlimited models only - does NOT fit 2-door JK Wrangler
• 4WD models only
• Sold as a pair (set of 2 front coil springs)
• Factory coil spring mounting hardware is reused during installation
• Long Travel (JKU35BPHLT) and other Skyjacker lift kits for the JK Unlimited use these springs as OEM-matched front components

Features

• Dual-rate progressive spring design automatically transitions between a softer initial rate and a firmer secondary rate, delivering on-road comfort and off-road control in one spring
• Long travel geometry keeps the coil seated in the spring bucket at full droop, preventing coil pop-out during maximum articulation on the trail
• Maximizes suspension articulation for improved axle droop and traction on uneven terrain
• Higher-strength chromium alloy construction resists sagging, fractures, and fatigue over the lifetime of the spring
• Shot-peened during manufacturing to compress surface material and increase tensile strength for maximum durability
• Matched to OEM Jeep JK Unlimited spring rates for factory-quality ride character on paved roads
• Black powder-coat finish provides long-lasting corrosion protection against trail and weather exposure
• Backed by Skyjacker's Limited Lifetime Warranty

Specifications

• Position: Front
• Lift Height: 4 inches
• Spring Type: Dual Rate Long Travel Coil Springs
• Material: Chromium alloy steel
• Finish: Black powder coat
• Sold As: Pair (2 springs per set)
• Warranty: Skyjacker Limited Lifetime Warranty

Included Components

• 2x Skyjacker JKU40FDR Dual Rate Long Travel Front Coil Springs

Product Description

The Skyjacker JKU40FDR delivers 4 inches of front lift for 2007-2018 Jeep Wrangler JK Unlimited (4-Door) using a dual-rate long travel coil spring design engineered specifically for the Unlimited's wheelbase and spring geometry. Unlike standard single-rate coil springs, the progressive dual-rate design provides a compliant initial spring rate for everyday driving comfort, then transitions to a firmer rate under heavier load or articulation - giving the JK Unlimited both a smooth street ride and predictable off-road handling in one spring.

The long travel design is a key differentiator: the coil remains seated in its bucket at full suspension droop, eliminating coil pop-out during maximum articulation and ensuring consistent damping performance on challenging terrain. Built from shot-peened chromium alloy and matched to the OEM spring rate, these springs pair directly with Skyjacker shocks and lift kits for the JK Unlimited. Sold as a complete front pair - no additional springs required for the front axle.