Constant velocity joint (CV joint, or popularly “grenade”) is one of the key elements of the transmission of front-wheel drive and all-wheel drive vehicles. It transmits torque from the gearbox to the wheels at different angles, ensuring smooth rotation even when cornering. But when it comes to outer CV joint, many drivers are confused: where is it located, what does it look like and why does it break?

In this article we will figure out where exactly the outer CV joint is located, how it differs from the internal one, and how to independently diagnose its malfunction. You will also learn what symptoms indicate wear and tear on the grenade, and what to do if it starts to “crunch.” And for those who are planning a replacement, we have prepared step-by-step instructions with nuances for different types of cars.

What is an outer CV joint and why is it needed?

Outdoor CV joint (Constant Velocity Joint) is the mechanism that connects the drive shaft to the wheel hub. Its main task is to transmit torque from the transmission to the wheels no power losseven when the wheel turns or bounces on bumps. Unlike the inner CV joint (which is attached to the gearbox), the outer one works under more severe conditions: it is subject to impacts, dirt and high loads during sharp turns.

Structurally, the outer CV joint is ball or tripoid mechanism (depending on the car model), enclosed in a durable case with anther. It is the boot that is the most vulnerable place: if it tears, dirt gets inside and the hinge quickly fails. On most modern machines (from VW Golf up to Lada Vesta) ball CV joints are used, and tripod ones are more often found on internal joints.

Why is the outer CV joint important? Because he:

  • 🔧 Wears out faster internal due to constant angular loads.
  • 🚗 Affects handling: Failure may cause the wheel to lock.
  • 💰 Cheaper to replacethan internal (but requires timely diagnosis).
📊 How often do you check the condition of CV joints?
Never checked
Once a year
When a crunch appears
Only when changing oil

Where is the outer CV joint: location diagram

The outer CV joint is located from the wheel side — it is attached directly to the hub. To find it, just:

  1. Raise the car on a lift or hang the front wheel (on the side where the fault is suspected).
  2. Turn the wheel all the way left or right (depending on the side).
  3. Behind the wheel rim you will see drive shaft (aka “half shaft”), and at its end there is a CV joint housing with a boot.

Visually, the outer CV joint looks like metal “pear” with a rubber cover (boot), secured with clamps. If the boot is torn or covered with oil, this is the first sign of problems. On some models (for example, Renault Logan or Hyundai Solaris) The CV joint may be partially covered by a protective casing, but you can always feel it with your hand.

element Location How to identify
Outer CV joint At the end of the drive shaft, at the wheel hub Metal body with boot, 4–6 bolts for fastening to the hub
Inner CV joint At the gearbox Larger, often with tripoid mechanism
Boot Covers the CV joint Rubber or silicone case with clamps
Drive shaft Connects the inner and outer CV joints Long metal rod

If you are not sure that you have found the outer CV joint, try turning the wheel manually (with the car suspended). The hinge should rotate smoothly, without play or crunching. Any extraneous sounds or resistance is a signal for diagnosis.

💡

To accurately determine which CV joint is crunching (inner or outer), engage first gear and drive off with the wheels turned out. Crunching noise when turning is a sign of a malfunction outdoor hinge

Signs of a faulty outer CV joint

The main symptom of a worn outer CV joint is crunch when turning. But there are other signs that are often ignored:

  • 🔊 Clicking or crackling sounds when starting from a standstill (especially with the wheels turned out).
  • 🛑 Vibration on the steering wheel when accelerating or turning.
  • 💨 Torn boot with traces of lubricant (if the CV joint is already “dying”, the boot is usually torn).
  • 🚘 Pulling the car to the side when moving in a straight line (rarely, but occurs with critical wear).

The crunching occurs due to the fact that the balls or rollers inside the CV joint are worn out, and when turning they “jump” along the grooves. In the early stages, the sound appears only at maximum turn of the steering wheel, but over time it becomes constant.

⚠️ Attention: If the CV joint crunches already on a straight line, this means that it completely worn out and can fall apart at any moment. Operating the car in this condition is dangerous - the hinge may jam while driving!

On some models (for example, Ford Focus or Kia Rio) wear of the CV joint is accompanied knocking when overcoming obstacles (for example, when driving onto a curb). This is due to play in the hinge, which manifests itself under vertical loads.

What happens if you don't change a crisp CV joint?

If you ignore the crunching noise, the CV joint will eventually fall apart. This will lead to:

1) Loss of control (the wheel will lock).

2) Damage to the hub or drive shaft (repairs will cost more).

3) Emergency situation on the road (especially dangerous at speed).

How to check the outer CV joint yourself

Diagnostics of the outer CV joint does not require special equipment. You will need:

  • 🔧 Jack or lift.
  • 👁️ Flashlight (to inspect the boot).
  • 🖐️ Crowbar or crowbar (to check play).

Step by step instructions:

  1. Raise the car and remove the wheel (from the side of the suspected CV joint).
  2. Inspect the boot: if it is torn or covered with grease, the CV joint is already damaged.
  3. Check the play:
    • Grasp the hub drive shaft with your hand.
    • Swing it up and down and left and right. Play of more than 1–2 mm is a sign of wear.
  • Spin the wheel manually, listening to extraneous sounds.
  • Drive with your wheels turned out (in an empty parking lot) to hear a crunching sound.

    • Inspect the boot for integrity|Check the drive shaft play|Rotate the wheel manually|Test the crunch when turning|Assess the vibration on the steering wheel-->

    If you find play or crunching, the CV joint needs to be replaced. On most cars, the outer CV joint is non-removable - it is replaced entirely and not repaired.

    Step-by-step replacement of the outer CV joint

    Replacing an outer CV joint is a moderately difficult task. If you have experience working with a car, you can do it in 1-2 hours. To work you will need:

    • 🔧 A set of heads and keys (especially “30” for the hub nut).
    • 🔨 Hammer and chisel (for removing the old CV joint).
    • 🛠️ Puller for CV joints (optional, but simplifies the task).
    • 🧴 New lubricant for CV joints (for example, LIQUI MOLY LM47).
    • 🔄 New boot with clamps (if not included).

    Replacement instructions:

    1. Remove the wheel and unscrew the hub nut (after loosening it on the ground).
    2. Disconnect the tie rod and ball joint (if they interfere).
    3. Knock the CV joint out of the hub:
      • Use a hammer and a wooden spacer to avoid damaging the threads.
      • If the CV joint is stuck, a puller or WD-40 will help.
  • Remove the boot clamps and slide it along the shaft.
  • Knock down the old CV joint from the shaft (with a hammer through a chisel or a puller).
  • Install a new CV joint:
    • Apply lubricant to the shaft splines and the inside of the joint.
    • Put on the new boot and secure with clamps.
    • Snap the CV joint onto the hub and tighten the nut.
    • Reassemble everything in reverse order and check for any play.
    ⚠️ Attention: After replacing the CV joint be sure to check the wheel alignment angles! Even if you haven't touched the tie rods, removing the hub can affect the geometry.

    On some vehicles (for example, Audi A4 or BMW 3-series) To replace the CV joint, you need to remove the entire axle shaft. In this case, it is better to contact a service center - without a special tool, there is a risk of damaging the internal CV joint.

    💡

    The most common mistake when replacing a CV joint is incorrect installation of the boot. If the clamps are not tightened properly, the boot will fly off after 100–200 km, and the new CV joint will quickly fail.

    How much does it cost to replace an outer CV joint?

    The cost of replacement depends on the car make, CV joint type and region. On average:

    Service/Part Price (RUB) Notes
    CV joint (budget, for example, for VAZ 2110) 1 500–3 000 Chinese or domestic analogues
    CV joint (original, for example, for Toyota Corolla) 4 000–8 000 Japanese or European brands (GKN, SKF)
    Boot with clamps 300–800 It is better to take silicone - it lasts longer
    Grease for CV joints 200–500 Optimal: LIQUI MOLY or Molykote
    Work (in service) 1 500–4 000 Depends on the complexity (on some cars you need to remove the subframe)

    If you decide to change the CV joint yourself, the total cost will be 2,000–5,000 rubles (taking into account details). In a service with work it will cost 4,000–12,000 rubles, depending on the model.

    There is no point in saving on CV joints: cheap analogues last 2–3 times less than the original ones. For example, on Volkswagen Passat B6 a non-original CV joint can travel only 30–40 thousand km, while a branded one GKN departs 100+ thousand km.

    How to extend the life of an outer CV joint: prevention

    The service life of a CV joint depends not only on the quality of the part, but also on operating conditions. To avoid premature wear:

    • 🛣️ Avoid abrupt starts with the wheels turned out (especially in winter).
    • 🚗 Inspect the anthers regularly (every 10–15 thousand km).
    • 💧 Wash drive shafts when visiting a car wash (dirt accelerates wear).
    • 🔧 Use quality lubricant (not the usual “Litol-24”).
    • 🚘 Don't ignore the first signs of crunching — the sooner you replace it, the cheaper the repair will cost.

    Particular attention to the anthers: if they are torn, but the CV joint is not crunching yet, you can get by replacing the boot and lubricant. It's cheaper than replacing the entire joint. For example, on Ford Focus 2 replacing the boot will cost 1,000–1,500 rubles (versus 5,000–7,000 for a new CV joint).

    Also worth avoiding deep puddles and snow drifts: water and salt corrode the anthers, and the ice crust can tear the rubber. If you often drive off-road, install protective covers on drive shafts (they are available for many SUVs, for example, Nissan X-Trail or Mitsubishi Outlander).

    FAQ: Frequently asked questions about outer CV joints

    Is it possible to drive if the CV joint is crunching?

    Short term - yes, but the longer you wait to replace it, the higher the risk that the CV joint will fall apart while driving. The crunching noise means that the balls or rollers are already worn out, and the joint may jam at any moment. It is especially dangerous to drive with a worn CV joint at high speeds or when cornering.

    How to distinguish the crunch of a CV joint from the knock of a bearing?

    CV joint crunches only when turning (especially with the wheels turned out), and the bearing knocks constantly, and the sound intensifies with increasing speed. Also, the bearing usually produces vibration on the steering wheel, but the CV joint does not (until critical wear).

    How long does an outer CV joint last?

    The service life depends on the quality of the part and operating conditions:

    • Original CV joints (GKN, SKF) - 100,000–150,000 km.
    • High-quality analogues (Febi, TRW) - 60,000–100,000 km.
    • Budget Chinese CV joints - 20,000–40,000 km.

    The boot reduces its service life by 2–3 times if it is torn.

    Do I need to replace the CV joint in pairs?

    No, outer CV joints are replaced separately. Unlike internal ones, they are not interconnected, and wear of one does not affect the other. The exception is if you decide to change both for prevention (for example, with high mileage).

    Is it possible to restore the CV joint instead of replacing it?

    Theoretically yes, but in practice it is impractical. Outer CV joints are non-separable, and their “repair” comes down to replacing the lubricant and boot. If the hinge is already crunching, restoration will not help - it needs to be replaced entirely.