When are they tearing; when you wrap or when you are taking them off the trays?
If they are tearing when you take them off the tray, as mentioned earlier double wrap them. When you double wrap, the outer layer may stick the rack and tear, but the inner layer will stay in tack, so you won't loose your juices. If they are tearing when you wrap, I always wrap that first layer taunt. Tight enough, but not that tight that the bones will tear through; and you also need to be careful with the second layer. I warp that layer a little tighter.
Or you can use disposable pans, and foil over the top.