upper engine mount moving around causing vibration at idle

robocam · Post by **robocam** » 13 May 2009, 01:16

The upper engine mount on my 05 S80 2.5T is sliding around (forward and backward). If I accelerate, it gets stuck in one position and causes a bunch of vibration to be transmitted into the cabin at idle.

To fix this issue, I loosened the bolt in the middle of the upper mount while the car was running. Then I tightened it. Idle became smooth again. Then it moved again when I accelerated. I tried to make it really tight. I guess I'll have to tighten it even more? It seems like a pretty thick bolt. Do I have to worry about smashing anything if I make it too tight? I want it to quit shifting around. I thought about adding a star washer to each side. Is the middle of the mount solid metal?

I guess that mount has to take the full load of torque delivered to the drive wheels? after being multiplied several times by the transmission? Quite a bit it has to resist.

Post by **vegasjetskier** » 13 May 2009, 07:35

It's supposed to move. The center part is rubber. If you are getting too much movement, the rubber has probably cracked or one of the bottom engine mounts is broken, allowing the top of the engine to move too far. Can you post some pix of your mount so we can evaluate further?

robocam · Post by **robocam** » 13 May 2009, 09:12

Oh, it's a brand new mount installed by a Volvo dealer. What I mean is that the bolt is sliding forward and back in the oval shaped holes. Not the inner part of the mount moving, but the entire mount. Does that make any sense? It's the big long bolt that goes through the center of the mount. It's sliding in the bracket that's attached to the bar.

Post by **vegasjetskier** » 13 May 2009, 10:27

The torque on the bolt is supposed to be 80 Nm, or 59 ft-lbs.