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Get the Ride Height Right Without Sacrificing Factory Comfort
A lift that rides rough or sags after a season of wheeling isn't worth the mounting hardware. The RockJock RJ-144400-101 rear coil spring pair is engineered specifically for the Jeep Wrangler JL Unlimited, delivering a clean 3.5 inch lift while keeping compatibility with factory coil spring isolators. Each spring is finished in gloss black powder coat for long term corrosion resistance and built to work seamlessly with RockJock Johnny Joint suspension systems or other 3 to 5 inch lift setups, giving you a planted, predictable rear end whether you are running highway miles or crawling the trail.
Key Features
- Purpose built rear coil springs delivering a 3.5 inch lift on Jeep Wrangler JL Unlimited
- Free length of 17.460 inches for consistent, predictable ride height
- Gloss black powder coat finish resists chipping and corrosion
- Engineered to work with factory coil spring isolators, top and bottom
- Compatible with RockJock Johnny Joint suspension systems and other 3 to 5 inch lift kits
- Sold as a pair for a complete rear axle installation
- Part of the RockJock RJ-JLG001-101 Pro Edition JL Suspension System lineup
Fitment Table
| Year Range | Make | Model |
|---|---|---|
| 2018-2026 | Jeep | Wrangler JL Unlimited (3.6L V6 and 2.0T I4) |
Specifications
| Detail | Value |
|---|---|
| Brand | RockJock |
| Part Number | RJ-144400-101 |
| Location | Rear |
| Lift Height | 3.5 inch |
| Free Length | 17.460 in. |
| Finish | Gloss Black Powder Coat |
| Quantity | Pair (2 Springs) |
| UPC | Not published by manufacturer |
What's Included
- (2) RockJock 3.5 in. Lift Rear Coil Springs
About RockJock
RockJock 4x4 designs and manufactures heavy duty suspension, axle, and steering components engineered for serious off road use without giving up on road manners. Every RockJock coil spring is developed and tested as part of a complete suspension system, so lift height, spring rate, and ride quality are dialed in together rather than guessed at individually.
Related Parts on Our Site
- RockJock JL/JT Tow Bar Mounting Kit
- FOX Factory Series Rear Shock, 3.5-4in Lift
- RockJock Shifter Boot
FAQ
What is the RJ-144400-101?The RJ-144400-101 is a pair of RockJock rear coil springs built for the Jeep Wrangler JL Unlimited, delivering a 3.5 inch lift with a free length of 17.460 inches and a gloss black powder coat finish.
How much lift does this spring provide?This spring pair is designed to deliver a 3.5 inch lift at the rear axle when installed as a set.
Will this fit my Jeep Wrangler JL Unlimited?Yes, provided your Wrangler JL Unlimited is equipped with the 3.6L V6 or 2.0T I4 drivetrain. EcoDiesel, 392, and 4xe hybrid models use a different spring part number due to their unique weight distribution.
Do I need new bump stops with this spring?RockJock recommends installing properly matched bump stops when adding lift, since factory bump stops are calibrated for stock ride height and may contact the frame prematurely at 3.5 inches of lift.
Can I reuse my factory coil spring isolators?Yes, this spring is engineered to work with the factory upper and lower coil spring isolators, so no isolator replacement is required for installation.
Does this spring work with a full RockJock suspension system?Yes, the RJ-144400-101 is compatible with RockJock Johnny Joint suspension systems and is also part of the RJ-JLG001-101 Pro Edition JL Suspension System kit.
Is this spring sold individually or as a pair?This listing includes two rear coil springs, enough for a complete rear axle installation.
What finish does this spring use?Each spring receives a gloss black powder coat finish for long term resistance to rust and chipping in off road conditions.
Install Instructions
- Safely raise and support the rear of the vehicle, then remove the rear wheels.
- Support the rear axle with a jack and disconnect the sway bar links, brake lines, and any other components anchored to the axle as needed for clearance.
- Slowly lower the axle to relieve spring tension, then remove the factory coil springs and isolators if they are being reused, keeping isolators in their original orientation.
- Position the new RockJock rear coil springs onto the factory isolators, top and bottom, ensuring proper seating.
- Raise the axle back into position, reconnecting sway bar links, brake lines, and any other previously removed components.
- Install properly matched bump stops if not already upgraded for the new ride height.
- Reinstall the wheels, lower the vehicle, and torque all fasteners to manufacturer specification.
- Perform an alignment check and inspect all suspension hardware after the first several hundred miles of driving.
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