Shakey mirror glass

[VermontRotts]

The drivers side mirror on my 99 Suburban shakes as I'm going down the road. Is there away to tighten up the glass to get rid of the shake? I can see that there are objects behind me, but that is it.

 

Thanks

[bfrd22]

Is the glass loose or the head. I have to re-epoxly the mirrors back into the housings every 2yrs on the 94.

[VermontRotts]

The glass seems to be tight and the head barely moves. The vibration I get is just enough to make the cars noticeable but not clear enough to see what kind it is. I've noticed that the inside rear view also slightly vibrates, but the passenger mirror is clear. I feel no vibration either in the wheel or seat of my pants to think it is the truck.