importing animation issues

I’ve been animating objects in 3dsmax without using any bone structures ( simple animations of objects ). The animations work fine until I port them into unity and add them to the scene after setting up all the animation info. The problem is my animations are all screwed up and stretch out my object. I export them as an open collada file by the way.

I think using bones is the best way to go about it. It also adds consistency to any other animations you have, such as characters.