How to Replace a Control Arm

📋 Quick Facts

When the ball joint or bushings in a control arm wear out, the most common fix is to replace the entire arm as a preassembled unit. Replacement is 1-2 hours per side.

🛠 What You'll Need

• New control arm assembly (preloaded with ball joint and bushings) (control arm on Amazon)
• Socket set (typically 15, 17, 18, 21, 22mm) (socket set on Amazon)
• Breaker bar (breaker bar on Amazon)
• Torque wrench (capable of 100+ ft-lb) (torque wrench on Amazon)
• Ball joint separator or pickle fork (ball joint separator on Amazon)
• Floor jack and jack stands (jack stand set on Amazon)
• Penetrating oil (penetrating oil on Amazon)
• Mechanic gloves and eye protection (mechanic gloves on Amazon)

✅ Before You Start - Checklist

• Park on level, solid ground (no slopes, no soft dirt)
• Engine is at the correct temperature (cold or warm as specified)
• All tools and parts on hand BEFORE you begin
• Owner's manual nearby for torque specs and locations
• Safety: gloves, eye protection, hood propped open

📝 Step-by-Step Instructions

1. Loosen the lug nuts a half-turnOn the ground, crack the lug nuts loose.
2. Lift the vehicle and set jack standsStands under the chassis at the rated point. Remove the wheel.
3. Support the spring (lower control arm only)If you are replacing a lower arm and the spring sits on it, place a jack under the spring perch before unbolting anything. The spring stores significant force.
4. Spray penetrating oil on all control arm fastenersThe frame bolts, ball joint nut, and any sway bar link. Wait 10 minutes.
5. Disconnect the sway bar end link from the control armHold the stud with a wrench, turn the nut with another wrench.
6. Remove the cotter pin and ball joint castle nutLoosen until the nut sits at the end of the stud threads. Pop the joint loose with a separator. Then fully remove the nut.
7. Separate the ball joint from the steering knucklePull the knuckle outward to clear the ball joint stud. If a strut bolts to the knuckle, you may need to loosen it.
8. Mark the position of any eccentric (cam) boltsSome control arms use cam bolts at the frame to adjust alignment. Mark the cam position with paint or a punch before removing.
9. Remove the control arm frame boltsTypically 18-22mm. They may need a long breaker bar. Wiggle the bolt as you turn to break corrosion.
10. Drop the control arm out of the vehicleManeuver it around the brake rotor and steering linkage.
11. Compare old vs new control armBushing diameter, ball joint stud taper, sway bar attachment point, and any alignment cam slots should match.
12. Position the new control armHold it in place under the frame.
13. Hand-thread the frame boltsInsert all bolts and washers before tightening any.
14. Reconnect the ball joint to the steering knuckleSlide the stud into the knuckle, install the NEW castle nut, torque to spec (typically 60-100 ft-lb), and install a NEW cotter pin.
15. Reconnect the sway bar end linkTorque to spec (typically 25-50 ft-lb).
16. Torque the control arm frame bolts WITH THE SUSPENSION LOADEDLower the vehicle to ride height (or use a jack to load the arm to ride-height position) BEFORE final torque. This is critical - torquing with the arm hanging will pre-stress the bushings and cause early failure. Typical torque: 80-130 ft-lb plus an angle turn on torque-to-yield bolts.
17. Mount the wheel, lower fully, and torque lug nutsLug nuts to spec.
18. Get an alignment immediatelyControl arm replacement changes camber and caster. Drive gently to the alignment shop.

✅ After You Finish - Verify Checklist

• No tools left in the engine bay or under the car
• Test the system you worked on (start, drive, check, etc.)
• Look for leaks or drips after 5 minutes of running
• Record the date and mileage in your service log
• Recycle or properly dispose of any old parts/fluids

🔗 Related Guides

❓ Frequently Asked Questions