Everybody has great ideas, but no one knows whether they will work or not. So when you propose a change, some will make a prediction on whether it will work or not, while others will wait to see what happens before getting behind it or not. Lines will be drawn and sides will be taken.
This is another opportunity to lead by example - if you saw me do it instead of hearing me talk about it, wouldn't you feel more strongly about it?
The difficulty about 'doing' when you are a manager is that by doing you might find out that your idea didn't work after all ... but that's also something that can bring people together.