how do you tell if the wheel bearings are bad on a 2004 chevy malibu. We just had ours replaced as per goodyear graham tire. I saved the old parts to have them inspected by someone else
Mostly it is an analysis by diagnosis to determine the faulty part. Typically pitting, blackening or bluing or looseness are the prime indicators.
It might be hard to tell once the bearing is taken off. The method used to remove it can damages it. Usually when wheel bearing start to go bad, the first thing you notice is an unusual noise. Sometimes it is a sort of a low volume “whrrrrp”… “whrrrp” sound, often only heard when turning at low speed. As the problem progresses, it turns into a growling sound, sort of like the sound made when you drive on a road with a rough surface. “grrrrrrrrrrrr”.
Was it front or rear bearings?
Wheel bearings are usually replaced on these cars for one of two reasons: either to turn off an ABS light or due to pitting or galling of the bearings, which cannot be seen, but can be felt and heard. Most people compare the sensation of driving on bad bearings to driving on rumble strips: steady roaring and sometimes a feeling of roughness at speed. They can also be loose in the hub, but this is not as common as the other two reasons to replace them on this car. Road noise is the most common reason to replace these bearings, so if you used to have a lot of road noise and now you don’t, the problem was solved.
Bearings are checked, always while the wheel is elevated, by
(1) checking the wheel for looseness while shaking. Really bad bearings will allow play.
(2) spinning the wheel by hand and listening
(3) turning the wheel by hand and feeling for roughness
(4) removing the wheel and turning the hub by hand. Sometimes roughness can be felt with the weight of the wheel off of the hub that cannot be felt with the wheel mounted.
Usuallyy these checks are done in response to an oscillating humming/grinding sound thats been gradually developing that oscillates in synch with the car’s speed. The sound plus the checks are usually difinitive, but sometomes it’s a gut call.