2009 Mazda 5 Bearing Issue?

[linuxology]

My 2009 Mazda 5 (154k miles) had a bad passenger rear bearing, causing a mud-tire sound. Replaced it, but the sound's still there, maybe slightly better, but sound is still there 60-70 mph especially under acceleration.

Driver's side rear bearing has no wobble or noticeable noise when spun compared to passenger. Front bearings also seem fine. Tires have good tread and no obvious issues.

Given the persistent sound and difficulty pinpointing it, should I replace the driver's side rear bearing anyway? Any other ideas on what might be causing this persistent hum? Are there any better ways to pinpoint? Thanks!

 

[Propflux01]

Move that rear tire to the front and see if the noise follows. Many times those worn bearings will allow the wheel to move around ever so slightly to put a bad pattern on the tire.

 

[rob0781]

Sometimes you can't always see or hear it. Spin the wheel by hand and hold the coil spring with your other hand if its bad you'll feel it in the spring

 

[Kurtatron]

When I bought my Scion xD, it had a wheel bearing growl. I tried all the usual tests to identify it. Swerving and breaking.

After thinking it was the driver side rear, I replaced it only to find the growl remained. Turned out it was the passenger side.

I only determined this after spinning the bad bearing by hand and hearing a slight metal grinding sound.

your situation might be similar.

 

[K-Man]

Usually you should replace items such as tires, brakes, and bearings in pairs on the same axle. If one side goes, replace the other side at the same time. The reason is, of course, if one has worn out or failed, the one on the other side is probably ready to go too.

Another thing to think about: was the new bearing prelubed and sealed, or should it have been greased before installation? Was that done?