2005 XC70 Vibration

[BuffaloSabre]

I recently purchased a 2005 XC70 with 74,000 miles on it. The previous owner regularly visited the dealer for maintenance and repairs. The vehicle carries the Volvo issued extended warranty through 100,000 miles. The car is in very good condition overall, and is generally tight mechanically.

Now, my reason for this post: At speeds approaching ~ 65-70mph, there is a mild to moderate vibration, and it persists through 80mph. I have yet to drive the car at any faster speeds, but I highly doubt it would lessen at a higher speed. It is felt mainly in the seat and relatively faintly in the steering wheel. When I quickly let off the accelerator, or shift to neutral, the vibration does not seem to go away. At times, I can feel a light vibration at lower speeds as well.

Considering that the previous owner had new Goodyear tires installed by a mobile company that installed them at her place of business right before she listed it for sale, I felt pretty confident that a good 4-wheel spin balance was going to correct this problem. The front passenger wheel was found to need 2 oz balance weight correction and the front driver 1/2 oz (not really all that bad in my opinion, having knowledge of balancing concepts). I was told that both rear tires were within tolerance. It seem that this may have taken the edge off the vibration, but it is definitely still there and not acceptable to me.

I believe that she had a 4 wheel alignment performed within the last 6 months or so, but I do recognize that it's probably the next appropriate step in the process of elimination. The car will maybe drift ever so slightly to the driver's side, but not much at all. I have my doubts that misalignment is the root cause of this vibration.

I am leaning towards suspension, wheel bearing(s) in my own mind, but I am far from a qualified auto mechanic. I will likely be going to the dealer with this problem, especially given the warranty is being transferred to me. I just want to be prepared when the time comes. I want this corrected properly on my first visit to the dealer, and I would also rather not pay for the repair.

Comments?

Thank you!

Kirk
1985 250 Wagon
1992 240 Sedan
2005 XC70

[z28chuck400hp]

check front half shafts; the right one is longer and most common cause of vibration...also check drive shaft going to the rear..there is a carrier bearing in the middle of the shaft... it has a rubber bushing around it.Look at the bushing and see if it is shot or sticking out...if it is, its the cause ...sadly you have to replace the whole unit as the bearing canot be changed.. about $900.00 for the part. I had the same problem in my 2001.. replaced right shaft and it got better but still not right. When I mashed the gas the vibration got worse.. then I found the rubber around the drive shat carrier was sticking out. Had my local shop inatall new Volvo shaft, (I have a bad back,and they have a lift) cost about $1200.00 for the whole thing.. good luck.. let me know how you make out.