📋 Quick Facts
Time
2-3 hours per side
Difficulty
Hard
Tools
8 needed
Cost to DIY
$80-280
CV axles fail by torn boots (grease leaks out, dirt gets in) or clicking on turns (worn outer joint). DIY replacement is a 2-3 hour job per side. Always replace as a complete assembly, not just the boot, unless caught very early.
🛠 What You'll Need
- New CV axle (correct part number, side-specific) (CV axle on Amazon)
- Large breaker bar (axle hub nut is 200+ ft-lb) (breaker bar on Amazon)
- Axle hub nut socket (typically 30-36mm) (large socket set on Amazon)
- Pickle fork or ball joint separator (ball joint separator on Amazon)
- Pry bar (24-36 inch) (pry bar on Amazon)
- Floor jack and jack stands (jack stand set on Amazon)
- New axle nut and circlip (if not included) (axle nut on Amazon)
- Drain pan for transmission fluid catch (drain pan on Amazon)
⚠ When NOT to DIY thisThe axle hub nut is torqued to 200-280 ft-lb. Removing it requires a long breaker bar and a helper applying the brakes. Pulling the inner CV from the transmission can release ATF or differential oil - have a catch pan ready. Some all-wheel-drive cars (Audi quattro, Subaru, AWD Honda) have additional complexity. If the inner joint is rust-welded into the transmission, professional help may be needed to avoid damaging the transmission case.
✅ 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
- Loosen the axle hub nut before lifting the carWith the car on the ground (wheels still loaded), use a breaker bar with the proper socket. Have a helper press the brake hard. Crack the nut a half-turn. Do NOT remove yet.
- Loosen the lug nuts a half-turnOn the ground, crack the lug nuts loose.
- Jack up the car and set jack standsLift the front, set stands on the chassis pinch welds. Remove the wheel.
- Position a drain pan under the transmissionPulling the inner CV releases trans fluid (manual) or differential oil (some automatics). Catch it.
- Fully remove the axle hub nutIt should come off easily after being cracked loose. Set it aside (or buy a new one if torque-to-yield).
- Disconnect the lower ball jointRemove the ball joint pinch bolt or cotter pin + castle nut. Use a pickle fork or ball joint separator to pop the ball joint loose from the steering knuckle.
- Swing the knuckle outwardWith the ball joint disconnected, pull the steering knuckle outward to clear the axle from the hub. May need to remove the tie rod end too for clearance.
- Push or tap the axle out of the hubThe outer CV stub passes through the wheel bearing. May need a light tap with a soft hammer to break it loose. Use a puller if frozen in the splines.
- Pry the inner CV out of the transmissionPlace a long pry bar between the inner CV joint and the transmission case. Pry firmly outward. The internal circlip will pop out of its groove. Have the drain pan ready - fluid will leak.
- Remove the old axle from the carPull it straight out through the hub side. Note the orientation and length for the new axle.
- Compare old and new axleLength, spline count on both ends, circlip groove, and ABS reluctor ring (if any). Many vehicles have left-side and right-side specific axles - confirm before installing.
- Install the new circlip on the inner stubIf a new circlip came with the axle, install it in the groove. Make sure it sits fully seated.
- Insert the inner CV into the transmissionPush the inner stub into the transmission with a firm, straight push. Should click into place as the circlip seats. Tug back to confirm it is locked.
- Pass the outer CV through the wheel hubPull the steering knuckle out, slide the outer stub through the hub, and let the knuckle pivot back.
- Reconnect the lower ball jointPush the ball joint stud back into the knuckle. Reinstall the pinch bolt or castle nut + new cotter pin. Torque to spec (typically 30-50 ft-lb).
- Install and torque the axle hub nutHand-thread the new (or original) hub nut. Mount the wheel, lower the car, then torque the hub nut to spec (typically 180-220 ft-lb). Set the cotter pin or stake the nut as required.
- Top off transmission fluid and test driveRefill any fluid you lost from the transmission. Drive a short test: listen for clicking on turns. None = success. If the new axle clicks already, the inner CV may not be fully seated.
✅ 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
How do I know my CV axle is bad?
Classic symptom: rhythmic clicking that gets worse on tight turns (outer CV joint). Vibration on acceleration (inner joint). Grease splattered on the wheel well or inside the wheel = torn boot.
Can I replace just the boot instead of the whole axle?
Only if caught very early (boot freshly torn, no contamination, no clicking). Once dirt has entered, the joint is compromised even if it has not failed yet. A complete reman axle is usually only $30-50 more and far less work.
Do I need to replace the axle nut?
On most cars, yes - it is torque-to-yield (designed for single use). Some cars allow reuse. Check service info. New axle nuts are $5-10.
Do I need an alignment after replacing a CV axle?
Not strictly required if you did not disturb tie rods or camber adjustments. If you disconnected the tie rod end during axle removal, get an alignment.
My new axle is still clicking - why?
Common causes: defective new axle (sometimes reman quality is poor), insufficient grease in the boot, or the inner CV not fully seated in the transmission. Re-seat the inner stub firmly.
Should I do both sides at the same time?
Not required, but if one side has failed at 100,000+ miles, the other side is often close behind. Doing both is convenient if you have the time and budget.