Bearings always come in handy when reducing friction. As small as they are, they can sometimes make the difference between life and death. In short, they are safety parts as much as they are service components. But like it is always the case with any component designed to reduce friction, they wear out. This is perfectly normal. What is not normal though is having to change your bearings all the time. The frequency should be far apart especially if you hardly use your car regularly or you do not drive it over a long distance. Read on to learn more about what causes frequent bearing wear outs and what you can do to solve the problem.
When bearings are cooling after use, the air, lubricant and contracting metal create a vacuum that should be tightly held by the seals. If the seals fail to hold the vacuum, the sealed hub or the bearing will such in air, water and debris. This can be devastating especially in parts where salt is used on the roads. As these contaminants get in and circulate through the car grease and between the bearings and races, the components wear before eventually losing their metallurgy.
You’ll notice that the steering may wander or it may become lose. There could also be some noise coming from the wheel area. The noise may worsen as you turn and completely disappear at certain speeds. Be keen not to confuse the noise with pops and clicks that are often produced by worn out over CV joints on FWD cars. A faulty outer CV joints only makes noise when turning, not when driving straight ahead. Once the bearing is completely worn, the wear rate is accelerated by seals that can no longer keep out contaminants. Increased heat will therefore find it easy to expel lubricants and cause catastrophic failure.
You’ll have to take your Porsche for inspection to find out if this is the problem. Then keep in mind that apart from improper adjustment, vehicle overloads and the kind of terrain you drive your Porsche on can also take a toll on your bearings. Note that the most rampant failure pattern for bearings emanate from the passenger side of the vehicle. This happens because the passenger side bearings become exposed not just to stagnant water in the gutter but also debris. So if the bearings on the driver’s side fail first, examine the ones at the passenger side. Failure may be imminent.
Bearing components are usually heat treated so as to harden the metal. Unfortunately, the heat treating cannot penetrate to the core. The bearing wears through the outer layer before the softer part follows. Experts refer to this kind of fatigue as ‘spalling’. It causes the metal to suddenly come off in flakes. Note that with tapered Porsche roller bearings, excessive pre-load usually mimics this damage. The best solution here is to take your Porsche for inspection and to change the bearings as often as recommended. Be sure to also avoid inferior bearings with low quality steel and poor heat treating. They always end up wearing and spalling prematurely.