How to Install Zone Offroad J-Flex Adjustable Rear Upper Control Arm for 0-4 in. Lift (97-06 Wrangler TJ) on your Jeep Wrangler

CONGRATULATIONS on purchasing a set J-Flex Adjustable Control Arms from JKS Manufacturing. We are committed to providing you with the best products available and your satisfaction is our first priority.

PLEASE READ these Installation Instructions carefully, and save them for future reference, as they contain important installation and maintenance information.

Important

COMPATIBLE WITH original 4-link suspension configuration and vehicle ride height up to 6.0”.

SUSPENSION COMPONENTS THAT HAVE RUBBER BUSHINGS must be tightened with vehicle on level ground and at normal ride height. The springs must be supporting the weight of the vehicle when the hardware is torqued; or else ride comfort could be affected and premature bushing wear may occur.

REFER TO FACTORY SERVICE MANUAL for information and procedures not covered in these instructions.

Install Adjustable Control Arms ONE AT A TIME for easiest alignment of mounting hardware.

1. REMOVE ORIGINAL REAR UPPER SUSPENSION ARM

Raise and support the vehicle chassis with jack stands positioned in front of the rear lower suspension arm brackets.

Raise and support the rear axle housing with a hydraulic jack.

HINT: The axle housing should be evenly supported, with the suspension at normal ride height. Do not attempt removal or installation with the suspension extended, or the axle drooped, as this will place tension on suspension arm mounting hardware.

Remove the parking brake cable and ABS wiring (if equipped) from upper suspension arm.

Remove the rear upper suspension arm nut and bolt from the axle housing bracket. Retain the original mounting hardware.

Remove the nut and bolt from the chassis rail bracket. Retain the original mounting hardware.

Remove original rear upper suspension arm.

2. SET CONTROL ARM LENGTH

J-Flex control arms are fully collapsed when supplied from JKS and must be adjusted to the desired lengths before installation.

Determine ideal control arm length for your application by considering factors such as:

Factory arm length is 13-1/4"

Lower control arm length

Pinion Angle

Rotate adjustable end of control arm until the desired length is achieved.

Adjust corresponding control arm to exact same length.

3. INSTALL CONTROL ARM

The control arms are side specific. The flex end will be mounted to the frame with the brake line tab facing towards the center of the vehicle and pointing slightly down.

Mount the flex end of the control arm to the chassis rail bracket with the grease fitting facing down.

Install the original mounting bolt and finger tighten the nut. DO NOT torque mounting hardware until instructed.

Mount the rubbing bushing end of control arm to the axle housing bracket.

Install the original mounting bolt and finger tighten the nut. DO NOT torque mounting hardware until instructed.

HINT: If mounting bolt is difficult to install due to misalignment of Control Arm bushing with mounting bracket, either (1) adjust height of axle housing with hydraulic jack, (2) move axle housing into position with a heavy-duty ratchet strap, or (3) temporarily disconnect track bar until mounting holes align.

Attach the parking brake cable and ABS wiring (if equipped) to the upper control arm with the factory hardware.

4. TIGHTEN MOUNTING HARDWARE

Once all adjustable control arms have been properly installed, lower the vehicle to the ground until coil springs are supporting the full weight of vehicle.

Using a torque wrench, tighten the mounting hardware to the factory torque specifications for your vehicle.

Wrangler TJ, 1997-06

Tighten bolt at REAR axle and chassis brackets to 55 ft-lbs.

Grand Cherokee ZJ, 1993-98

Tighten bolt at REAR axle and chassis brackets to 55 ft-lbs.

Tighten jam nuts while ensuring the flex end remains square to the chassis bracket.

5. POST-INSTALLATION INSTRUCTIONS

J-Flex control arms are supplied pre-lubricated, although it will be necessary to add more grease after they have been installed on the vehicle. Refer to maintenance section for specific lubrication instructions.

Maintenance

J-Flex control arms should be greased regularly as part of vehicle maintenance schedule. Lubricate using non-pretroleum based grease and a hand-pump grease gun.

RUBBER BUSHINGS MUST NEVER BE LUBRICATED, as doing so will impair performance and longevity.