'99 Legacy GT wagon "body boom"

[mwatt]

my '99 Legacy GT wagon (auto trans) has developed a booming/rumble noise inside the vehicle at 60 mph....not a shimmy or shaking...it's a throbbling rumble sound that disappears above or below 60, but it's obnoxious at exactly 60 mph. All is quiet at 55mph and at 65 mph.

 

Car has 164K miles; I've heard that the rear driveshaft u-joints being worn can cause this.....has anyone else experienced this?

Edited October 5, 2010 by mwatt

[GeneralDisorder]

Sounds like a wheel bearing to me.

 

GD

[mwatt]

thanks for the response....in this case I'll have to say no---it's not a bearing because they make a distinct "rolling/grind/howling" sound when they fail. This is a booming/throbbing inside the passenger compartment--only at one speed. I'm still leaning toward a rear driveshaft problem; just wanted to hear if anyone else has replaced u-joints (or the driveshaft because, to my knowledge, you can't get replacement u-joints from Subaru.) in an effort to fix this kind of problem

[johnceggleston]

thanks for the response....in this case I'll have to say no---it's not a bearing because they make a distinct "rolling/grind/howling" sound when they fail. This is a booming/throbbing inside the passenger compartment--only at one speed. I'm still leaning toward a rear driveshaft problem; just wanted to hear if anyone else has replaced u-joints (or the driveshaft because, to my knowledge, you can't get replacement u-joints from Subaru.) in an effort to fix this kind of problem

 

buy a used one , it will probably out last your car.

 

ww.car-part.com

[NV Zeno]

Just throwing it out there...possibly a rear wheel bent or out of balance?

[Suba9792]

.... have you had a balance and rotation lately? I really don't think it would be the u-joints you would hear it and! feel it at most speeds, my opinion, have a balance and rotation done, or new tires, alignment. And check the front axles for any heavy play, also check the rear drive shaft, as I haven't heard of those failing much I guess it wouldn't hurt. The one thing I have noticed owning these cars... balance rotation ON time is key to it riding well, it puts alot of strain on the AWD when you have a tire/wheel out of wack. Mine has ALOT of road noise, but that is because its a Lego Brighton sitting on 14's and my axles are starting to get bad, I have a bad tie rod end so alignments dont help..But what has is keeping them rotated for even wear, soon the work will be done.

[Ricearu]

does it matter if the windows are up or down, try having your passenger push the center of the roof up while it's doing its thing. My legacy did that, it would rumble then go bbbwwwoooonnngg as the roof would buckle in (like a dent in a hood) I could roll up the windows and as soon as I hit the ac switch, it would BANG!!! and pop back up.