Front Wheel Bearings?

[GoldenOne]

Driving home today I noticed a howling noise which grew in loudness with speed. I saw over on bmwe34.net that it very well be the front wheel bearings but I'm curious to know how to tell which side as gone bad. Or should I just replace both sides while I'm at it? TIA

[TC535i]

If you turn right, your car leans over and puts a load on the left side... yeah? Well, if that wheel gets quiet... it's the bad bearing. Alternatively, if load is taken off a wheel (inside wheel... think of a car picking up a wheel in a turn, this is just a more extreme example of the load removal) and the noise increases, this is also a bad bearing.

Keeping that in mind, drive around and see which wheel quiets down when you load it up... you've found your culprit.

[Blitzkrieg Bob]

since they are probably both the same age and wear.

[rob101]

yeah just do both. because otherwise you'll be revisiting the same problem in the near future on the other side.

[Ross]

Turning loads each side of the bearing, so unless you can tell which side the growl emanates from the turning thing will only tell you if it's an inner or an outer.
Assuming this in front, try jacking it up, backing off the brake pads so the wheel spins freely and listen. Sometimes you can even feel the roughness.

[GoldenOne]

Thanks for the info guys I will drive around to see which one it is but I probably will do both. Do the rears have a similar setup?

[Blitzkrieg Bob]

Thanks for the info guys I will drive around to see which one it is but I probably will do both. Do the rears have a similar setup?

more involved, with axle stubs and speciality tools

[icesoft]

Yeah, front's are easy, changed mine in under 30 mins/side last weekend, just make sure you've got a torque wrench that goes up high enough to crank down the collar nut.

When you buy the bearings, make sure you buy new nuts and dustcaps. They're cheap parts and make the job go much quicker, rather than worrying about getting the old ones off in one piece

[AutoXr]

Check your tires too. My cheapo Fusions are incredibly noisy. Not knowing any better, I would be looking at front bearings too. It's just the tires.