Puckillustrations/Stock.Adobe.Com (Puckillustrations/Stock.Adobe.Com)Living in a climate as I do that gets lots of snow and constant freezing and thawing temperatures, the roads in Pennsylvania develop nasty, teeth-chattering, wheel-busting, tire-bursting potholes. While physical damage can be easily spotted, the real danger lies in hidden damage to steering, suspension, bearings and axles. A clunking noise after hitting a pothole is a straight-up warning telling you something is wrong.In my over 50-year career as a master ASE and General Motors auto technician, I replaced hundreds, if not thousands of tires, drive axles, constant velocity joints and just about every steering and suspension part on a car due to drivers hitting a pothole. In fact, in 2022, 44 million drivers paid for damage caused by potholes.Read along while a master technician and an auto parts recycler explain what noises to listen for, and offer simple, practical checks you can make yourself to increase safety and lower the risk of catastrophic—expensive—mechanical failures due to damage caused by driving over potholes.Damaging Effects Of Winter PotholesWhen water penetrates porous asphalt, it expands and contracts during winter’s icy freeze-and-thaw cycles. This causes asphalt to heave and contract, deform and break apart, leaving behind potholes.AdvertisementAdvertisementDriving over a pothole can push steering parts, suspension components or CV axles past their expected tolerances. A jolt that bends a control arm—even a fraction of an inch—can throw your car’s alignment angles out of whack. This places additional stress not only on tires and axles, but wheel bearings as well.Compounding the problem, rubber stiffens in cold temperatures decreasing a tire’s ability to absorb the energy of hitting a pothole, transferring more impact to the suspension. “Rubber shrinks when cold and can place excess pressure on metal parts they are trying to isolate from other metal parts,” said ASE and Toyota Master Technician Joe Simes. Add in mud, dirt and corrosive road salt that will worsen any existing weaknesses, especially a torn CV boot, creating the perfect storm for part failure.Car Noises And Signs You Should Never IgnoreCars make lots of noises, especially in the deep freeze of January and February. Most are from normal operation and go away as your car warms up while driving. But there are several noises you must never disregard, particularly after hitting a pothole, including:Clunking when driving straight over bumps or into a raised driveway could mean damaged, worn or bent bushings (your car has dozens of bushings), ball joints, tie-rod ends, MacPherson struts or shock absorbers.Metallic knock or slapping on wheel rebound could signal a bad MacPherson strut mount, cracked or broken coil spring or coil spring insulator, bent sway arm or stabilizer links or cracked anti-roll, sway arm or leaking hydraulic damper.Deep thud with steering pull indicates a bent wheel, or loose or shifted sub-frame.Clicking, grinding or popping when turning usually signifies a damaged or worn-out CV joint that has probably lost all its grease from a torn CV boot. A worn or failing wheel bearing can also cause these noises while turning.Rhythmic thumping can be caused by a broken tire belt or a bad wheel bearing. A continuous humming, whining or droning coming from your wheels while driving, cornering that increases with speed, is usually caused by a bad wheel bearing,” said Simes.What “Clunking” Can Actually MeanClunking indicates one of two things. Either two parts in close proximity that should be isolated from each other are touching, or a single component with too much free play is shifting or moving excessively while driving.AdvertisementAdvertisementFor example, a worn or missing sway arm bushing will permit the sway arm to “clunk” against its mounting bracket and car chassis when accelerating, stopping or going over a bump. As my colleague Karuna Eberl puts it, “One thing’s for sure, if you have a suspension noise that suddenly disappears, there’s a good chance the component is broken and disconnected from the rest of your car.”Why Ignoring Noise Leads To Axle Or Bearing Hub FailureAs Simes mentioned, a humming or whining noise means some part or component on or in your car is loose, sloppy, weak or damaged. Axle bearing, hubs, and CV joints are designed to spin and should have “zero” side-to-side movement. On modern front- and four-wheel-drive cars, wheel bearings are sets of precisely machined, hardened steel ball bearings or straight roller bearings (shaped like a can of soda). The balls, or rollers, are encased in a “cage” that supports the bearings, allowing them to spin freely.A sharp impact from hitting a pothole can dent or crack the bearing race or flatten a bearing roller. As the wheel rotates, the roller repeatedly hits the dent or crack, or the flat spot rubs against the race, causing the parts to wear. With every rotation, tiny flakes or chips of metal break off the surface of the race or roller, intensifying bearing play. This creates rhythmic growls or hums. The increased play (movement) results in excess hub bearing wobble and vibration, and the axle splines wear abnormally.Once a bearing develops play, the hub will no longer hold the axle perfectly centered. This causes your car’s steering and braking to become unstable or pull to one side. Temperatures will increase as the bearing continues failing. This can lead to axle or CV joint grease leaking or breaking down. Increased temperatures can also warp the hub, damage the CV joint, possibly creating a second part failure, that is, of course, if the hub bearing doesn’t completely come apart first, causing the wheel to come off while driving.Quick Checks You Can DoKazimieras Urbonas, automotive expert at automotive part recycler Ovoko, suggests, “Go over a speed bump with the radio off. Hearing a dull ‘thud’ is normal, but a sharp, metallic ‘clunk’ or a rattle can be the first sign of pothole damage.”AdvertisementAdvertisementTest for your shocks and MacPherson struts by pushing down hard (jounce) on the bumper two or three times. Your vehicle should come to rest after one rebound. Replace them if your car keeps bouncing, you hear knocking, or you see fluid leaking from a shock. Defective shocks/struts increase stopping distance and make your car dangerous to handle on icy roads. Wheel bearing noise can also mimic engine noise,” said Simes.Simes adds that, if your car has a tachometer/RPM gauge, “Watch the RPM gauge as it increases when accelerating. Take your foot off the accelerator and listen as RPMs drop. If the noise is still there, it’s coming from a wheel, axle, hub or bearing, not the engine.” Look under your car around source of the noise. Look for shiny or other wear marks, rust stains, or worn paint from loose, damaged, bent or worn-out parts rubbing against each other.When It’s Safe To Drive, And When To PulloverAfter hitting a pothole, find a straight, flat road, and when safe, loosen your grip on the steering wheel slightly for a second, then step on the brake pedal. “Pullover and call for a tow of your car immediately if the steering wheel is no longer ‘centered,’ pulls or drifts [especially if erratically] to one side while moving or braking. Something is likely to have been bent or damaged from the impact,” said Urbonas. “It’s not safe to drive.”Preventing Pothole DamageSlowing down before hitting, staying away from the curb, or safely driving around a pothole are the best defenses against damage from them. If you see what looks like standing water, treat it as if it were a pothole; it could very well be an eight-inch crater (which I have driven into on more than one occasion) that can easily cause suspension parts to brutally strike each other.AdvertisementAdvertisementSimes says maintaining proper tire pressure can help prevent pothole damage. “Visually inspect your tires for abnormal wear or squeak when turning, and don’t ignore noises that weren’t there before hitting a pothole,” he says. If you cannot avoid a pothole, slamming on the brakes during the impact transfers vehicle weight to the front wheels, increasing the possibility of damage.After the winter, have your car’s suspension aligned, wheels balanced and undercarriage visually inspected by your mechanic. “Taking your car in for repairs before things get worse is the best thing you can do to help keep a simple repair from turning into a major expense,” said Urbonas.FAQsHow much does it cost to replace an axle or bearing hub?The average cost to replace a sealed wheel hub bearing is around $350 per wheel. However, depending on the make and model, the shop labor rate ($47 to $215 per hour, according to AAA) and any additional damage could easily push the cost per wheel beyond $1,000.However, on some vehicles, it can be less than $100 per wheel. And you can save hundreds on labor if you DIY. If you don’t have the tools, most auto parts stores will lend you the specialty tools and equipment needed.What other damage can hitting a pothole cause?Besides tire, wheel, steering, suspension and frame/chassis damage, hitting a pothole can damage brake dust shields, twist a brake caliper, causing brakes to pull or lock up, overheat or wear prematurely. Other issues include damage to sensitive electronics, as well as ABS, ride height, stability or TPMS (Tire Pressure Monitoring System) sensors. All of which will trigger a dashboard warning light if damaged.ExpertsJoe Simes has over 25 years’ experience in the automotive industry as an ASE and Toyota Master Technician, a Pennsylvania Department of Education certified automotive technology instructor, as well as a PA certified emissions and safety inspection instructor and inspector. He is currently an automotive technology instructor at North Montco Technical Career Center in Lansdale, PA. Joe was also the former deputy fire chief and training officer for Montgomery County, PA (retired). (Interview Mar 6, 2026)Kazimieras Urbonas is a motoring expert and Supplier Excellence Manager at Ovoko, one of the world’s largest digital marketplaces for used (recycled) auto parts. He specializes in vehicle mechanics and wear-and-tear, helping drivers understand damage caused by harsh road conditions and identify reliable replacement components. (Electronic communications Mar 6, 2026)SourcesAAA: “Car Repair Labor Rates Explained” Mar 5, 2026AAA: “Drivers, Beware: Potholes Pop Up Early This Year” Mar 3, 2026FOX Weather: ”Spring pothole season is here: Steps to avoid that tiring annual headache” Mar 5, 2026Jim DeLeo, Northeast Division Manager for Hunter Engineering Company Interview Mar 6, 2026Look Up A Plate: “8 Alarming Pothole Statistics Every American Needs to Know” Jan 15, 2026State Farm: “When potholes become costly” Mar 5, 2026The Hartford: “Potholes: The Sneaky Road Hazards That Can Really Leave a Dent in Your Day” Mar 5, 2026RELATED:Do You Know What That Little Button on Your Seat Belt Is For?What Those Lines on Your Backup Camera Really Tell YouHere’s What The Small Panel On Your Car’s Front Bumper Is For
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