So I have been battling a vibration ghost.

My wifes 2003 S60 with 130k started to vibrate when accelerating, usually in 5th gear (automagic), about 6wks ago. It started as something soft and occasional, so we did like all owners and ignored it. After a week or two it got real bad so I threw the car up and found a collapsed front mount. I replaced it and the vibrations did not go away, but reduced significantly. They started coming back this week so I checked the mount I had installed...collapsed (stupid internet mount). The upper mount was also toast. So 120$ later I have two locally sourced Hutchison mounts and I installed them yesterday. HUGE difference at idle and at low speeds, gone is any sign of vibration. Now there is a distinctive vibration (with a rubber dampened feel) when accelerating between 55 and 65-70 mph. the moment you let off the gas or decrease the rate of acceleration it goes away. I am good at accelerating and not getting it to happen, my wife is good at getting it to happen.

So WTF!!! The two new mounts and the torque limiting mount (center front of car between sub frame and engine) are all new. The fluid filled mount located behind the front grill looks good (not leaking) and I can't see the other mount, but there is no fluid stain on the sub frame below it.

I am at a loss. could the T-belt have skipped a tooth? Could the tranny be going? I know I need to replace the pass side tranny side drive shaft boot, which is torn, could that be it? Maybe something drivetrain and not motor mount?

Any thoughts, suggestions, or insight would rock.

Getting good mounts does make a diffference. Your new vibration would well be the CV joint if the boot is torn. It makes sense since it is not rpm or gear related, but just speed.
Replace the entire axle, not new lube and boot. Much easier and safer.

Klaus
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Proud owner of a 220S. If I had more room, I would have more Volvos.

Good to know - I didn't realize there was such a difference with the cheap mounts. I'll keep that in mind.

I agree with Klaus on the CV boot thing too. If you've already got a rip you might as well do the whole axle. The water/air/dirt/etc will already have caused enough damage in there that you should just go all the way and get that thing out of there in favour of new parts.

You could save yourself some money on the other side and replace only the boot. It is a messy job and basically the same amount of work as swapping in a new axle as you have to remove the old axle to do the boot... I chose to do the boots on my V70 because I got it before the boots ripped - they just looked old so I did them. It wasn't too tough, but it would have been a long day if I wasn't pulling the suspension apart for something else (replacing lower control arm).

Still, do yourself a favour and junk the axle with the torn boot.