08 impreza OB sport wheel bearing diagnosis help

[lukewarm54]

I have above stated car with a growl while driving. It sounds at times to be coming from front at certain speeds, occasionally it seems like it's coming from the back.

Noise seems like it's on right side of vehicle

I jacked up vehicle and checked all wheels for play-nothing in any wheel. I then spun each wheel listening and then trying to feel any notchiness in bearings, again nothing. All I hear is slight brake rub

RR bearings replaced about 2 years ago with Moog bearings

Noise has gotten worse in last few weeks so I assumed wheels would give away which is bad but still not a clue. Tires are relatively new and I ran my hand over them feeling for feathering, they seem fine. Noise is worse between 30 to about 50 mph but still heard above 65. No binding noise or banging in parking lot so I don't think it's viscous coupler like my old outback.

Car is a 5 speed MT

Car has about 250k miles but is well cared for and gets serviced either by me or mechanic.

Not sure really where to go from here

[nvu]

it does sound like bearings.  try spinning the wheels while holding on the the spring coil.  it amplifies the vibrations. if there is a bad one, you'll feel nominal vibrations on the other wheels and really different vibrations on the one with a bad bearing.

[idosubaru]

Turn very sharply on sweeping turns at 40+ mph both to the left and right. If noise goes away under that side loading it’s the bearing.  Not just during the sweeping turn. But even do a quick 1 second extra few degree turn while doing the sweeping turn to the right or left while turning. Noise will disappear during that momentary sharp turn at speed.  This is the most consistent test I’ve seen on ones that are relatively loud. 

havw someone else drive and sit in the rear seat or hatch area and front passenger seat  it should be obvious which corner it is  

An infrared temp gun on each rotor will tell you if one is much hotter than the other side. Take lots of readings at same point on rotor as the heat dissipation and readings aren’t consistent. But you’ll see a pattern and 30-100 degree difference. This doesn’t always work either but catches some that pass the “play” and typical bearing tests

Moog bearing has a very good chance of failing again. I avoid aftermarket bearings and I’ve still seen numerous failures. Moog, Timken…even the “good” ones you just never know. I’ve never seen an OEM Subaru bearing repeat failure. And I use them far more often and on any car that’s likely to see a lot more years/miles  

If you use after market bearings they have a lower failure rate if properly torqued.  The Subaru bearings can be zipped on and abused with an air gun and not torqued and walked in back forth to a rusty hub and never fail. I don’t use a torque wrench on Subaru bearings. Not one failure. Aftermarket will fail if they’re treated roughly, not installed straight and torqued properly.  Which speaks to their quality and all the more reason to avoid. But they are cheap so if you use aftermarket again clean everything up, install it straight and clean and torque it properly.

Edited April 5 by idosubaru