My 2008 Cobalt makes a loud hum when I'm driving that increases with speed. I just purchased new tires and changed my brakes and rotors and haven't noticed any improvement over 5K miles. I believe that I have a bad wheel bearing on the driver side which I want to replace. I was looking on Rockauto's website and they have an Axel Bearing and Hub Assembly and a Wheel Bearing listed. Both are in the same price range, but I'm sure there is a difference. Any ideas on what that might be?

 

I had the same problem with my 07, drivers side hub assembly was replaced under warranty at the dealership, might want to have them take a look.

 

I'm already through my warranty. Heavy highway driving.

So my question still stands: What is the difference between an Axel Bearing & Hub Assembly and a Wheel Bearing?

 

Well i may not be the best to answer so you may want to verify, but if that sound gets louder the faster you go it's likely the wheels bearing, which is pressed right onto the hub assembly (ie can't just replace the $12 wheel bearing) when i checked last (novemberish before i found out it was covered under waranty) it was about $200 shipped for the hub assembly. You'll most likely need an alignment after installing. Don't take just my word though, i still have lots to learn.