Control Arm Bushings on Jeep Wranglers — When to Replace Them

What Control Arms Do

Control arms connect the axle to the frame and control the axle's position in both the horizontal and vertical planes. The upper and lower control arms work together to locate the axle front to back, control the pinion angle, and manage the axle's movement during suspension travel. Each control arm has a bushing at each end that allows the arm to pivot as the suspension moves. These bushings are made of rubber or polyurethane and wear out over time.

The lower control arms take the most abuse because they handle the braking and acceleration forces. The upper control arms handle mostly lateral forces. On JK and JL Wranglers, there are four lower control arms and two upper control arms. On TJ Wranglers, there are four lower and four upper arms.

Signs of Worn Bushings

Worn control arm bushings cause a variety of handling problems. The most common symptom is a clunking noise from the front or rear suspension when going over bumps. You may also notice the vehicle wandering at highway speeds requiring constant steering correction. Brake dive and acceleration squat become more pronounced because the control arms are allowing the axle to move more than it should.

Inspect the bushings by looking at the rubber material around the metal sleeve of the bushing. Cracking, tearing, or separation of the rubber from the metal means the bushing needs replacement. Push up and down on the bumper or use a pry bar between the axle and the control arm to check for excessive movement. A bushing that has significant movement with moderate force is worn out.

Replacement Options

You can replace just the bushings or the entire control arm. Replacing just the bushings is cheaper but requires a press to remove the old bushings and install new ones. Replacing the entire control arm is more expensive but easier — the old arm is unbolted and a new one with fresh bushings is installed. For stock replacement, use Moog or OEM control arms with rubber bushings.

Many Wrangler owners upgrade to adjustable control arms when replacing worn bushings. Adjustable arms allow you to fine-tune the pinion angle and wheelbase, which is important for lifted Wranglers. They also come with polyurethane bushings that last longer than rubber. The trade-off is that polyurethane bushings transmit more vibration and noise into the cabin. For a daily driver, stick with rubber bushings unless you need the adjustability for a lift.

Bottom Line

Worn control arm bushings cause clunking, wandering, and vague handling. Inspect them regularly and replace them when the rubber shows cracking or separation. For stock Wranglers, replace with Moog or OEM rubber bushings. For lifted Wranglers, adjustable control arms with polyurethane bushings provide better durability and allow pinion angle correction.

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