Please Identify This Animated Film

I'm trying to find an animated jungle animal film that came out about 15-20 years ago....a group of animals lives were in danger and they had to move elsewhere...there was a stampede scene that was so loud, I remember telling my friends with young children not to bring them to see this, because the thundering noise of the stampede would scare them to death. There was a female elephant character who was very old and slow, and we were all afraid she wouldn't make it. But she came through, when there was an obstacle to be moved, and being the biggest animal there, only she could save the day ! Does anyone remember this ?