Many car owners and technicians ask: Why do bearings fail prematurely with low mileage, increasing repair costs? Premature failure usually stems not from poor quality alone, but from a mix of working conditions, assembly, usage and maintenance. Based on real repair cases, here are the six most common causes.

1. Seal failure leading to water and dust ingress

   The most common cause in daily use. Aging or damaged seals let rain, mud and road water enter, diluting grease and causing corrosion and abrasive wear—leading to noise quickly.
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3. Improper assembly causing hidden damage

   Violent hammering, wrong tools or uneven pressing leave indentations on raceways and deform internal structures. Damage may not show immediately but causes rapid failure within a few thousand kilometers.
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5. Lubricant loss or degradation

   Factory-filled special grease resists heat, water and wear. Prolonged high-speed, high-temperature operation causes grease to volatilize or carbonize, resulting in dry friction and overheating seizure.
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7. Overloading and aggressive driving

   Constant heavy loads, frequent sharp turns, rapid acceleration and hard braking exceed design loads, speeding metal fatigue and flaking.
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9. Environmental corrosion

   Coastal salt spray, winter road de-icing salt and corrosive chemicals gradually erode bearing metal and seals, leading to gradual failure.
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11. Mismatched parts selection

    Low-grade bearings with incorrect precision, load rating or sealing cannot withstand original operating conditions, resulting in very short service life.