2003 Forester- whine from passengers rear at highway speed

[Stevo F]

My latest Subaru noise is an a steady whine which starts around 40 MPH with a lower pitch and the pitch gets higher as you go faster. This has becomes really noticeable over the past several thousand miles (we bought it used at 223K miles). 2003 Forester XS, automatic, currently with 232K miles

I tested the car in front wheel drive with no change in the noise (which makes me thinking not likely to be a differential or u- joint issues).

I put the spare on the passengers rear with no change in the noise. The tires as all in decent physical condition and even wear (Michelin Defenders with 60% tread).

I have receipts showing both front and driver's rear wheel bearings were replaced by the previous owner, but I believe the passenger's side rear is original. However, the noise doesn't really change on turns, except a little scraping noise on right turns (when there is the most force on the passengers rear, but that's been there since we bought it and I know the backing plate is a bit rusty).

I.m thinking of sending my son back to college on Monday in this car since his Legacy GT has the airbag light on again and I want him in something safe until we can diagnose that problem. I want to make sure this isn't going to become a serious issue down the road if we let my son take it.

Please got to the link below and have a listen. A bit of background noise, but you can hear the lower pitched whine.

 

[GeneralDisorder]

Wheel bearing. Always is in these. 

GD

[gbhrps]

Stevo F,

Get a mechanic to get the car in the air with it running and in gear, and a driver in the driver's seat. Using a stethascope on each of the rear wheel hubs, the culprit will come to light at various speeds.

[el_freddo]

7 hours ago, gbhrps said:

Get a mechanic to get the car in the air with it running and in gear, and a driver in the driver's seat. Using a stethascope on each of the rear wheel hubs, the culprit will come to light at various speeds.

Why bother? Front bearings replaced already, rears wouldn’t be far off if they’re factory fitted. Money better spent on labour replacing the bearing if not going the DIY route. 

My first thought was a bearing before looking at the video or reading GD’s post. 

All the best with it - I’d replace both rear bearings to a) know the history of both rear bearings and b) potentially save a second trip to the mechanics and further down time on the vehicle. But I’m a DIYer so it’s your call (I’d do both regardless of one being replaced or not).

Cheers 

Bennie

[Stevo F]

9 hours ago, el_freddo said:

Why bother? Front bearings replaced already, rears wouldn’t be far off if they’re factory fitted. Money better spent on labour replacing the bearing if not going the DIY route. 

My first thought was a bearing before looking at the video or reading GD’s post. 

All the best with it - I’d replace both rear bearings to a) know the history of both rear bearings and b) potentially save a second trip to the mechanics and further down time on the vehicle. But I’m a DIYer so it’s your call (I’d do both regardless of one being replaced or not).

Cheers 

Bennie

Thank you. Actually have a receipt showing the drivers rear bearing was done 2 years along with a new backing plate. The previous owner actually had ordered both rear backing plates so I have the passengers rear one ready to go when/ if the hearing gets replaced 

Edited January 5, 2020 by Stevo F

[idosubaru]

Bearing.

If needing backing plates suggests rust, have the blue wrench ready or sell tickets for your own personal WWE.