XC70 intermitant engine vibration

[spannermedonky]

Hi Peoples,

Does anyone know of a common engine mount failing in the 2.5T geartronic XC70 range?
My beloved speedy swede has developed a vibration mainly at idle or intermittently at low revs. She has covered 115K miles if that helps, recently had both front ball joints replaced and the angle box sleeve at Christmas, and the crank case vent and the throttle body cleaned....
At first I just noticed a random clonk when pulling away or changing from reverse to forward, I put it down to axle ping but the driveshaft bolts are fine. Also when starting the car there is a reasonably load clonk, a bit like the timing being a bit too far advanced when the engine first catches. Engine is otherwise smooth.
Now I have quite a load vibration from the engine bay area, not metal on metal but quite load inside the vehicle and noticeable outside, I was hoping the infamous top mount had failed, the rubber had started to fail but when I changed it at the weekend it was in fact still serviceable, I did however take the opportunity to fit a powerflex mount to let some of that 5 pot growl into the car which it does rather well (it does vibrate the seats a bit at idle giving rise to that glassy eyed look!)
If I rock the engine back or forward by rotating the torque mount by hand I can get the vibration to stop, I did not try this before changing the top mount but I am sure it would have done the same.
I checked the front engine mount at the weekend, it looks like new, also checked the right hand side mount which seems quite firm when I lever it with a big screwdriver, I assume the petrol engines don’t use vacuum mounts. Also I checked the lower torque mount which the smaller rubber did look quite soft. If anything the offending noise seems to be coming from gearbox end of the engine bay but I ran out of time to check for any gearbox mount issues. I do need to negotiate nearly 70 sets of traffic lights every day so I guess an engine / gearbox mount issue is likely, also there are a good number of sunken manhole covers and potholes in downtown Sheffield.
I did also check the exhaust in case of any broken hangers but looks fine.
Any ideas? At the moment I am hoping if I ignore it, it might go away.

Sorry for the long post.

[DinoS80]

Hi, surprised you didn't get any replies to your threat? Maybe it was removed since already old...
Anyway, I have an S80-2005 and a XC70-2006. Both 5cyl engine, virtually the same including the supports.
The S80 is smooth without any vibrations even though the top mount is significantly damaged. The XC70 vibrates annoyingly especially at low revs. Replaced all 5 engine mounts without any improvement!
So, now I'm wondering what solved your problem? Gearbox mounts? Are there any other anti-vibration parts I overlooked? Is the harmonic balancer (belt pulley) a possible cause?

Ideas very welcome,
Enjoy you Volvos!