1995 Volvo 850 GLT Wheel Vibration

[kw1999]

I seem to have the weirdest problem. Back in May, I replaced my entire strut assemblies - left and right. Immediately after I replaced the struts, I had an unexplainable steering wheel vibration that only appeared between 22-25 MPH, and only if your foot was on the gas. After that, it would disappear completely. Cruising speeds on the highway? Absolutely nothing. Just that weird vibration post-strut replacement at 25 MPH. I had an alignment done, which did absolutely nothing for both the vibration or direction of the vehicle. In fact, the car still pulls to the right (indicative of perhaps another problem).

Last month, I was driving along, and I heard a very prominent hum from the right front section of the car at precisely 35-39 MPH. After having a professional mechanic listen to it, he attributed the hum to a wheel bearing that was on its way out. I just got the right wheel bearing replaced yesterday, which brings me to the reason I am posting this. Driving down the road, although the hum is now gone, seems much worse. Not only has the weird vibration in the steering wheel at 25 MPH intensified, it re-appears at around 45 MPH, and very prominently. It appears to remain all the way up to 70 MPH, but I have yet to test beyond that. Weirdly, this time around it seems more violent when your foot is off the gas, or when the transmission shifts into the lower-revving 3rd/4th gears (doesn't seem to vibrate as much when the engine is revving higher), or even if you throw it into neutral. I am completely baffled as to why this is. One would think that having an alignment done AND replacing the known defective wheel bearing would at least reduce the symptoms, but no. The first drive back from the mechanics and the vehicle feels worse than when it went in. I can't figure it out.

Possible causes: Left front wheel bearing is also bad, CV joint/axle is bad?

Some background: Vehicle has ~260,000+ miles (OD gear was broken until I fixed it this year), well-maintained, but the left CV boot is torn, which could potentially mean it needs a CV joint/axle.

Thanks for any help!

[tryingbe]

What did the mechanic suggest about the vibration? Were all the wheels balance recently?

[Cees Klumper]

I would check the driveshaft inner bearings.

[dosbricks]

How long has the CV boot been torn? Has it throw the grease? Is it dry/dirty inside?
In other words, start with the symptom that presents itself, since it's in need of repair anyway.