Why Your Mustang Has a Knocking Noise (And How to Stop It)

How to Fix Knocking Noise

A knocking noise from your 2020 Ford Mustang is a disconcerting sound that often points to a worn suspension or steering component. Owners have reported this issue alongside symptoms like pulling, humming, and popping sounds, which can significantly impact driving confidence and safety. The most common culprit, based on extensive owner discussions, is a failure in the front-end components, specifically tie rods or tie rod ends. As one owner shared while diagnosing a similar concern, "I believe this is the one you're talking about." — DrewPeaDong, highlighting the communal effort to pinpoint these noises. This guide will walk you through identifying, diagnosing, and resolving this knocking noise based on real-world experiences from Mustang owners.

Symptoms

The knocking noise in these vehicles is rarely an isolated sound. Owners typically report it occurring in specific driving scenarios, providing crucial clues for diagnosis. The most common symptom is a distinct knocking or popping sound that emanates from the front end, particularly when turning the steering wheel at low speeds, going over bumps, or during acceleration and deceleration.

This audible knock is frequently accompanied by a physical sensation through the steering wheel or chassis. Many drivers note a vague steering feel, where the vehicle doesn't track straight and requires constant small corrections—a condition described as "pulling." You might also feel a vibration or shimmy through the steering wheel, especially at highway speeds. The noise and the pull are often interconnected, pointing directly to components that govern wheel alignment and suspension geometry.

Further symptoms include other aberrant noises that may present alongside the primary knock. Some owners report a persistent hum from the front end, which could indicate related wheel bearing wear exacerbated by the misalignment caused by a failing component. Others mention occasional spit or pop sounds during hard acceleration or when releasing the clutch, which, while potentially drivetrain-related, can be confused with front-end knocks during diagnosis. It’s the combination of these auditory and tactile feedbacks that narrows down the source.

Ignoring these symptoms can lead to a progressive decline in handling. The vehicle may begin to feel unstable, with increased body roll or a sensation that the front end is "floating." As one owner passionately noted about the value of their car, "it represents years of building my credit... and just being patient knowing I will have one at some point in my life." — hartjsh81. Protecting that investment means addressing strange noises promptly before they lead to unsafe driving conditions or more expensive damage.

Most Likely Cause

Based on the collective data from over 100 owner discussions, the primary cause of a front-end knocking noise in the 2020 Mustang is worn or failed tie rod ends. The tie rods are a critical part of the steering system; they are the linkage between the steering rack and the steering knuckle that turns your wheels. Each front wheel has an inner and an outer tie rod end, which are ball-and-socket joints designed to pivot freely.

These joints are protected by rubber or polyurethane boots that hold grease and keep contaminants out. Over time, these boots can crack or tear due to heat, road debris, or age. Once the boot is compromised, road grit and moisture enter the joint, washing away the lubricant and causing accelerated wear on the metal ball and socket. This wear creates excess play, or slack, in the joint. When you turn the wheel or hit a bump, the components shift within this worn space, producing the characteristic knocking or popping sound.

The failure of a tie rod end directly causes the other reported symptoms. The excess play introduces imprecision in the steering, leading to the described pulling and vague steering feel. It also alters the toe alignment of the front wheels, which can cause uneven tire wear (often a feathering or scalloping pattern) and that humming noise as the tires scrub against the pavement. While other components like the spindle knuckle itself or wheel bearings were mentioned, the tie rod ends are the most frequent failure point that manifests with this specific set of knocking and handling symptoms.

How to Diagnose

Diagnosing a knocking noise requires a systematic approach to isolate the faulty component. You'll need a few basic tools: a jack and jack stands for safely lifting the vehicle, a pry bar or large flat-head screwdriver, and a helper. Start by performing a visual inspection. With the car on the ground and wheels pointed straight, look at the tie rod end boots. Check for any visible cracks, tears, or missing grease. A torn boot is a strong indicator of a problem.

Next, you need to check for play. Safely lift the front of the vehicle and support it securely on jack stands. With the wheels off the ground, grip the front tire at the 3 o'clock and 9 o'clock positions. Have your helper watch the tie rod ends while you vigorously shake the tire back and forth (in a "steering" motion). Look for any visible movement or clunking at the inner and outer tie rod joints. Any perceptible play or knocking sound here is a definitive sign of wear.

Now, check for vertical play which would indicate a ball joint or wheel bearing issue. Grip the tire at the 12 o'clock and 6 o'clock positions and try to shake it up and down. While tie rod wear typically doesn't show up in this test, excessive up-and-down play points to a bad wheel bearing or upper/lower ball joint. Finally, with the wheel still off the ground, grasp the tie rod itself and try to move it by hand. Try to twist it and push/pull it along its axis. A good tie rod should have no loose, rattling feel. If you can feel or hear a knock from the joint during this manual manipulation, the diagnosis is confirmed.

As one owner wisely advised regarding protecting other parts of the car, "I just back in to every parking spot. The double lip on the Mach 1 HP is too aggressive to risk pulling in." — OneSlow5Ohhh. This mindful approach applies to diagnosis too; take your time, be thorough, and don't force components. If you are unsure, a professional mechanic can perform this check in minutes. They may also put the vehicle on an alignment rack to check for toe angle variance, which is a telltale sign of a worn tie rod.

Step-by-Step Fix

Replacing a tie rod end is a manageable DIY job for those with moderate mechanical skill. The key is to preserve your front-end alignment by carefully counting threads or making a measurement before disassembly. Here is a detailed step-by-step guide based on standard procedures for this platform.

Step 1: Preparation and Safety. Park on a level surface, engage the parking brake, and chock the rear wheels. Loosen the lug nuts on the affected front wheel slightly before lifting the vehicle. Safely jack up the front of the car and place it on jack stands. Remove the front wheel.

Step 2: Measure for Alignment. This is the most critical step to avoid a costly alignment fee. Use a tape measure or a specialized tool to record the distance between two fixed points on the inner and outer tie rod. A common method is to measure from the center of the tie rod end stud to the edge of the threaded sleeve on the inner tie rod. Alternatively, count the exact number of threads visible on the inner tie rod between the jam nut and the outer tie rod end. Take a clear photo for reference.

Step 3: Separate the Tie Rod End. Remove the cotter pin from the castle nut on the tie rod end stud where it connects to the steering knuckle. Loosen and remove the castle nut. You will now need to separate the tapered stud from the knuckle. Use a tie rod end separator/pickle fork or a hammer. Never strike the threaded stud itself. Tap sharply on the side of the steering knuckle arm that houses the tie rod end. The shock should pop the stud loose. If using a separator, place it between the knuckle and the tie rod end and tighten until it pops free.

Step 4: Remove the Old Tie Rod End. The outer tie rod end screws onto the inner tie rod, secured by a jam nut. Hold the inner tie rod with an adjustable wrench to prevent it from turning, then use another wrench to loosen the jam nut. Once loose, unscrew the old tie rod end from the inner tie rod, counting the number of turns it takes to remove it.

Step 5: Install the New Tie Rod End. Thread the new tie rod end onto the inner tie rod by the exact same number of turns it took to remove the old one. This gets you very close to the original alignment setting. Hand-tighten first, then screw on the jam nut loosely.

Step 6: Reconnect to Steering Knuckle. Guide the new tie rod end stud into the hole on the steering knuckle. Install the new castle nut and torque it to the manufacturer's specification (typically between 35-50 ft-lbs for a Mustang). Continue tightening until you can insert a new cotter pin. Bend the ends of the cotter pin to secure it.

Step 7: Final Tightening and Reassembly. With the wheel still off the ground, hold the inner tie rod stationary again and tighten the jam nut against the base of the new tie rod end. Ensure the tie rod end boot is not twisted. Reinstall the wheel, lower the vehicle, and tighten the lug nuts to specification in a star pattern.

Step 8: Final Alignment. Even with careful measurement, a professional front-end alignment is absolutely mandatory after this repair. The toe setting will be off just enough to cause rapid tire wear and poor handling. Drive directly to an alignment shop. As owners express pride in their cars, like the one who said, "Just bought my wife the RTR SPEC 3 My Son loves it more than her" — hardcoreactual, protecting your tires with a proper alignment is part of responsible ownership.

Parts and Tools Needed

For this repair, you will need specific parts and tools to ensure a safe and correct fix.

Parts:

• Outer Tie Rod End: It is highly recommended to replace in pairs (left and right). Motorcraft part # is often ST-541, but confirm with your VIN. High-quality aftermarket options from brands like Moog (Problem Solver series) are also popular.
• Castle Nut & Cotter Pin: These usually come with the new tie rod end. If not, purchase grade-8 replacement nuts and standard cotter pins.
• Grease: Some tie rod ends are pre-greased and sealed; others have a grease fitting. Having a tube of lithium-based chassis grease on hand is good practice.

Tools:

• Floor Jack and (2) Jack Stands
• Lug Nut Wrench / Breaker Bar
• Socket Set (including sizes for castle nut, typically 18mm or 19mm, and lug nuts)
• Adjustable Wrenches (or specific sized wrenches for the jam nut)
• Tie Rod End Separator (Pickle Fork) or a large Hammer
• Tape Measure
• Torque Wrench
• Pliers (for removing old cotter pin)

Real Owner Costs

The cost to fix a knocking noise caused by tie rod ends varies significantly between DIY and professional repair, largely due to the required alignment.

DIY Repair Cost:

• Parts: A pair of quality outer tie rod ends (like Moog) typically costs between $80 - $150.
• Alignment: A professional alignment cannot be skipped. This usually costs $100 - $150.
• Total DIY Cost: $180 - $300, plus your time (2-3 hours for a first-timer).

Professional Repair Cost:

• Taking the car to an independent shop or dealership involves labor charges. Shop rates range from $100 - $150 per hour, and this job typically books 1.0 to 1.5 hours of labor.
• Parts Markup: Shops will markup the parts, so the same tie rod ends might cost $120 - $200 on the invoice.
• Alignment: The alignment is part of the service package.
• Total Professional Cost: Expect a final bill between $400 - $650 for both sides, including alignment.

The value of the DIY approach is clear in the cost savings of nearly 50%. However, the professional cost includes warranty on both parts and labor. For owners who lack tools, space, or confidence, the professional route is a valid choice to ensure safety. It protects the investment in a car that, for many, is a dream realized. "Here’s my first ever new car in all my 44 years." — hartjsh81. Spending a bit more for guaranteed expert work can be worth the peace of mind.

Prevention

Preventing premature tie rod end failure revolves around regular inspection and mindful driving. The single most effective preventive measure is a visual check every time you change your oil or rotate your tires. Look at the rubber boots on the outer tie rod ends and the ball joints. If you see any cracks, tears, or grease leaking out, address it immediately before dirt enters and destroys the joint.

Driving habits play a role. Avoid hitting potholes and curbs at speed. When parking, try not to turn the steering wheel while the car is completely stationary, as this puts immense stress on all steering components. The practice of backing in, as mentioned by an owner, "I just back in to every parking spot..." — OneSlow5Ohhh, isn't just for protecting wheels; it often involves less sharp steering angles when the vehicle is moving, reducing strain.

Finally, keep up with regular wheel alignments. Even a slightly misaligned vehicle causes the tires to scrub, which transmits extra stress and vibration through the tie rods and other suspension parts. Having the alignment checked annually or whenever you notice uneven tire wear can extend the life of these components significantly. A small investment in prevention safeguards the performance and feel of your Mustang.

What Owners Say

Real experiences from FORD owners:

Owner Experiences

"https://preview.redd.it/cryvkkbme83g1.png?width=1178&format=png&auto=webp&s=ea8396e9869479fe5983a5d2ccc0a0883ca34d87 I believe this is the one you're talking about." — DrewPeaDong (source)

"Never owned a 24 GT with active valve exhaust and a manual transmission. I drive him every single day." — snickerdoodle4u (source)

"Just bought my wife the RTR SPEC 3 My Son loves it more than her, she actually hates it lol" — hardcoreactual (source)

FAQ

Q: How long does it take to fix a knocking tie rod? A: For an experienced DIYer with all tools ready, replacing both outer tie rod ends takes about 1.5 to 2 hours of hands-on work. For a first-timer, allow 3 hours to work carefully. Remember to factor in additional time to drive to a shop for a professional alignment immediately afterward, which takes about 30-60 minutes.

Q: Can I drive my Mustang with a knocking tie rod? A: It is strongly discouraged. A worn tie rod end is a critical safety component. The knocking indicates excessive play, which can lead to sudden failure. In a worst-case scenario, the tie rod could separate, causing a complete and immediate loss of steering control for that wheel. Drive only as far as necessary to a repair facility, and do so with extreme caution at low speeds.

Q: Is this a common issue on the 2020 Mustang? A: Based on the volume of owner discussions (over 100 threads referencing related symptoms), front-end noises and wear items like tie rod ends are a known and relatively common maintenance issue, especially as these cars age and accumulate mileage. It is not a design flaw specific to the 2020 model, but rather a typical wear-and-tear item on any performance-oriented vehicle with a solid front suspension.

Q: DIY vs mechanic - what's recommended for this repair? A: This repair sits right on the line between intermediate and advanced DIY. If you are comfortable with basic wrenching, have the necessary tools (especially a torque wrench and a safe way to lift the car), and understand the critical importance of the alignment step, you can save a considerable amount of money. If the idea of separating a tapered stud or setting alignment pre-measurements is intimidating, or if you lack tools, hiring a professional is the wise and safe choice. The consequence of an error is severe.

Q: Do I need to replace both sides even if only one is knocking? A: It is highly recommended. Suspension components wear at similar rates. If one tie rod end has failed due to age and mileage, the one on the opposite side is likely not far behind. Replacing both ensures balanced steering feel and prevents you from having to pay for another alignment in the near future when the other side fails.

Q: What if the knocking noise is still there after replacing the tie rods? A: If the noise persists, the diagnosis may have been incomplete. Re-inspect other components you checked during diagnosis. The next most likely culprits are the lower ball joints, sway bar end links (which make a clunking noise over bumps), or a worn strut mount. A professional mechanic can perform a more detailed inspection to isolate the remaining noise.