vibration in drivetrain

[89bk]

I've got a vibration problem that I need help with. Hopefully you can give me suggestions on what to inspect.

I've had my 98 Legacy wagon for about two months now. When I got it, the inner passenger cv boot was torn, so as a learning experience, I replaced the boot. I marked everything well (bearings, races, axles, etc.) when taking it apart so I'm pretty certain everything went back together as they were before I took it apart. But after reinstalling the axle, I noticed a vibration from low speed to interstate driving (it's worse at higher speeds). So, I figured I did the reassembly wrong so I bought a new axle (I went through 5 rebuilt/reman axles and they all did not fit--the splines on the inner axle were ground wrong) so I ended up buying a new axle (Empi brand, made in China) and installing that. Same vibration at same speeds, not a bit of improvement.

I don't want to start replacing everything by trial and error so I thought I'd ask to see if anyone has suggestions for me.

Oh, I did have all four tires balanced, then rebalanced and both times they "zeroed out" on the high speed balancer, so they're all perfectly balanced. The rims and tires are not out of round, the tire shop said.

The vibration feels like a juddering, a drive train that is out of balance somewhere. I feel it in the steering wheel and in the seat of my pants so I'm not sure if it's a cv joint, a driveshaft, or something that is out of balance.

Any thoughts?

[MCarp22]

Could it be from the wheel bearing? It could have been going bad, or the axle nut could have not been torqued properly.

[89bk]

The axle nut was torqued to about 135 ft lbs. before installing wheel (I say "about 135" because the torque wrench has accuracy rating of 4% + or - on the high end of the scale (max torque is 150 on my brand new Craftsman torque wrench from Sears). Is that the wrong spec? Bearing is not making any noise at all.

[jmgtp]

Can you feel the pulsations in the brake pedal when you hit the brakes at speed? If so consider warped brake rotor, possibly due to overtighted lug nuts. If the wheel bearing was torqued too tightly it would probably make a groaning/moaning noise.

[89bk]

No, there is no vibration or pulsing when the brakes are applied. And there is no moaning or groaning sounds at all anywhere. But the vibration not only can be felt but it can just barely be heard (it's such a low-frequency noise that I think I hear it).

[Huffer]

You had the wheels balanced, but did you have the car aligned?

[89bk]

No, car has not been aligned, not yet, at least. I thought about that but in the past, every car I've ever driven (and I've driven many) with the wheels mis-aligned has never had a vibration problem like what I'm experiencing.

On a previous Legacy I had, the alignment was off and a couple of struts went bad so the tires started feathering a lot. The tires (RE-92's) whined so loudly that back seat passengers got a headache. But there was no vibration. (I reduced the whining tremendously by jacking up each wheel and used my work knife to slice off the high spots--it worked! Soon after that I replaced the struts, got new tires, and an alignment.)

But perhaps I should look into a good alignment anyway.

[jjs316]

I have a bad vibration/wobble when i turn right going about 55-60, but only when i turn right, not straight or left. anyone know what this could be?

[Huffer]

I have a bad vibration/wobble when i turn right going about 55-60, but only when i turn right, not straight or left. anyone know what this could be?

Could be a loose brake pad

[jjs316]

i figured if it was something like that it would vibrate all the time and not just on right curves. ill check it out though. thanks

[deadlydave]

i figured if it was something like that it would vibrate all the time and not just on right curves. ill check it out though. thanks

I just had a very similar problem, when i turned left, there was a grinding noise. I thought it was a bearing starting to go, since that's the sound my bearings made before they were replaced. Turns out, the rear Driver's side brake caliper was not releasing all the way. The pads had been chewed up. The shop replaced the pads and the caliper, only ran me like $240.