What are the symptoms of a bad drive axle?

Common signs include unusual noises, vibrations, steering pull, and potential loss of drive. Early detection can prevent more extensive damage.

In automotive terms, a drive axle transmits torque from the transmission to the wheels and includes axles, CV joints, and related components. A failing axle can result from worn CV joints, torn boots, bending, or bearing wear, and symptoms vary by drive configuration.

Common symptoms to watch for

This list covers the most frequent signs drivers notice when a drive axle or its CV joints are failing. If you notice any of these, have the vehicle inspected.

• Clunking, banging, or popping noises when accelerating or decelerating, especially during changes in speed or direction.


• Clicking or popping sounds when turning, often indicating worn CV joints.


• Vibration or shuddering at highway speeds, which can come from a bent or failing axle or worn joints.


• Steering pull or a drifting sensation; the car seems to tug to one side.


• Excessive or uneven tire wear, particularly on the inner or outer edge, suggesting joint or axle issues affecting alignment.


• Grease leakage or a torn CV boot; you may spot shiny grease on the inside of the wheel or around the CV joint area.


• Loss of power or intermittent drive engagement; in severe cases, the axle may fail to deliver torque.

Not all signs mean the axle is imminently failing, but they warrant a professional inspection to determine if the axle, CV joints, or related components require service or replacement.

Causes and visual checks

Knowing the likely causes helps prioritize inspections and repairs. These issues can originate from wear, impact damage, or inadequate boot protection.

• Worn or damaged CV joints, especially the outer joints on front-wheel-drive vehicles, which cause clicking when turning.


• Torn or leaking CV boots that let grease escape and allow dirt in, accelerating joint wear.


• Bent or damaged axle shafts due to a collision, pothole, or curb impact, leading to vibrations and handling changes.


• Damaged wheel bearings or hub assemblies that can mimic axle issues, causing vibration and noise.


• Internal axle splines or splines in the hub wearing out, reducing torque transfer.

Addressing the underlying cause typically involves replacing the faulty CV joint or axle shaft, repairing the boot, or replacing nearby components. A professional mechanic can confirm with inspection and diagnostic tests.

When to seek immediate help

If you notice sudden loss of drive, grinding noises while driving, or the vehicle becomes unable to move, stop safely and seek roadside assistance. Driving with a clearly damaged axle can cause further damage or create safety risks.

Summary

In short, a failing drive axle shows up through noise, vibration, steering changes, and potential loss of drive. Early diagnosis and professional repair are key to preventing more extensive damage and ensuring safe driving.

How do you tell if it's a CV joint or wheel bearing?

A bad CV joint often causes a clicking or popping sound during turns, while a bad wheel bearing typically makes a constant humming, growling, or grinding noise that changes with speed. Other key differences include that a bad CV joint can cause vibrations or a clunk when accelerating and turning, and a failure may result in a broken axle, causing the car to lose power to a wheel. A bad wheel bearing may cause steering wheel vibration, a wobbly wheel, or the ABS warning light to come on.
 
This video demonstrates how to diagnose a bad wheel bearing by checking for play in the wheel: 40sWay of the WrenchYouTube · Mar 25, 2021
Bad CV joint

• Clicking or popping noise: This is the most common sign and usually occurs when turning, especially during sharp, low-speed turns. 
• Vibration: You may feel vibrations while accelerating, sometimes accompanied by a clunking sound. 
• Grease on the wheel: A torn CV boot can leak grease, which may be visible on the inside of the wheel. 
• Car pulling to one side: In severe cases, a broken CV axle can cause the vehicle to lose power to a wheel and pull to one side. 

This video explains the difference between a bad CV joint and a bad wheel bearing: 1mAuto V Fix YouTube · Nov 8, 2022
Bad wheel bearing

• Humming or growling noise: A constant, rhythmic noise that gets louder as you drive faster is a strong indicator. 
• Squealing or grinding: A high-pitched squealing or grinding noise can also signal a bad bearing. 
• Steering wheel vibration: A vibrating steering wheel can be a symptom, especially as you speed up. 
• Wheel wobble: You might notice a physical wobble in the wheel, which can also lead to uneven tire wear. 
• ABS or traction control light: A failing wheel bearing can interfere with the Anti-lock Braking System (ABS), causing the warning light to appear on the dashboard. 
• Uneven tire wear: The improper movement of a failing bearing can cause uneven wear on the tire. 

You can watch this video to see how to diagnose a bad wheel bearing by spinning the wheel: 55sEasy FixYouTube · Apr 16, 2020

How much does it cost to replace a CV axle?

The average cost to replace a CV axle is between $300 and $1,500, but can vary significantly based on vehicle type and the extent of the repair. Parts typically cost between $70 and $1,500, while labor costs range from $100 to $350 and take 1 to 3 hours. Costs for luxury or performance vehicles can be higher. 
Cost breakdown

• Parts: $70 to $1,500 depending on the vehicle make and model. 
• Labor: $100 to $350, taking 1 to 3 hours. 
• Total average: $300 to $1,500. 

Factors that influence cost

• Vehicle type: A standard sedan will be less expensive to repair than a luxury or performance vehicle. 
• Labor rates: The cost of labor can vary depending on your geographic location and the specific repair shop. 
• Extent of the damage: If only the CV joint boot is damaged, it can be cheaper to repair than replacing the entire axle. 
• Drivetrain type: Front axle replacements generally cost between $500 and $800, while rear axle replacements may be between $450 and $650. 

Why you should replace a CV axle

• Safety: A failing CV axle can lead to a loss of control. 
• Prevent further damage: Ignoring a bad CV axle can cause damage to other drivetrain components. 
• Prevent a breakdown: A broken CV axle can cause you to lose power to the wheels, potentially leaving you stranded. 

How do you know if your drive axle is bad?

If you have a CV axle bad, symptoms can include: Clicking or popping noises. This noise happens especially when making sharp turns, and it's caused by a worn-out joint where the balls inside can't move smoothly anymore. It's most noticeable when accelerating and turning.

What happens if your axle goes bad?

If an axle is bad, you may experience unusual noises (clicking, clunking, or grinding), vibrations or shaking while driving, and grease leaking from around the wheel. A failing axle can lead to reduced power, poor acceleration, and uneven tire wear because it misaligns the wheel. In severe cases, the axle can break completely, causing a complete loss of power to the wheels and potential loss of control.
 
This video explains the symptoms of a bad CV axle: 30sEasyAutoFixYouTube · Nov 5, 2022
Common symptoms of a bad axle

• Unusual noises: Listen for clicking, clunking, or grinding sounds, especially when turning. 
• Vibrations: You may feel a rhythmic shaking or rumbling in the vehicle that gets worse as you drive. 
• Grease leaks: Look for dark grease leaking from the wheel hub or under the car near the axle. 
• Uneven tire wear: A damaged axle can misalign your wheels, causing tires to wear out unevenly. 
• Steering issues: The steering wheel may feel stiff or unresponsive, or the car might pull to one side. 
• Power loss: You may notice the vehicle struggles to accelerate or seems to have less power than before. 
• Complete failure: If the axle breaks, the car will not be able to move at all, even if the engine is running. 

What to do

• Stop driving immediately: Do not continue to drive a vehicle with a bad axle, especially if you notice symptoms like vibrations or strange noises, as it can be dangerous. 
• Get it inspected: Have a mechanic inspect the axle to determine the extent of the damage. 
• Be prepared for a replacement: Depending on the damage, the axle may need to be replaced. A damaged CV boot can sometimes be repaired by replacing the boot and repacking it with grease, but if the joint is already worn, the entire axle will need to be replaced.