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

CONGRATULATIONS on purchasing a set of 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”.

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 FRONT UPPER SUSPENSION ARM

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

Raise and support the front 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 front upper suspension arm nut and bolt from the axle housing bracket.

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

Remove original front upper suspension arm.

Inspect the condition of the rubber suspension bushing that is pressed into the axle housing bracket and replace if cracked or worn.

NEW OE RUBBER BUSHINGS for the upper suspension arm brackets on front axle housing are available from JKS as PN SB03A238253.

HINT: Special factory tools PN 7932/7603/7604 (Miller Special Tools, 800-801-5420) are useful for removing and installing OE rubber bushings.

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:

OE suspension arm length is 15-1/8"

Length of lower control arm

Caster

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

Adjust corresponding control arm to exact same length.

3. INSTALL CONTROL ARM

Mount the flex end of the adjustable control arm to the chassis rail bracket with the greaseable fitting facing UP. Use OE hardware.

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

Mount the clevis end of adjustable control arm to the axle housing bracket. Use provided M10X80 hardware.

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.

4. TIGHTEN MOUNTING HARDWARE

Once all J-Flex 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

Tighten nut at FRONT axle and chassis brackets to 60 ft-lbs.

Grand Cherokee ZJ, 1993-98

Tighten nut at FRONT axle and chassis brackets to 55 ft-lbs.

Grand Cherokee WJ, 1999-04

Tighten nut at FRONT axle and chassis brackets to 60 ft-lbs.

Cherokee XJ, 1984-01

Tighten nut at FRONT axle and chassis brackets to 55 ft-lbs.

Comanche MJ, 1986-92

Tighten nut at FRONT axle and chassis brackets to 55 ft-lbs.

Tighten jam nut while ensuring the flex end remains square to the chassis mount.

5. POST-INSTALLATION INSTRUCTIONS

J-Flex control arms are supplied pre-lubricated, but it is 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 a nonpretroleum based grease.