Will sealing a garage door threshold help keep rodents out of my garage?

A garage door threshold sealant will help to keep rodents out of your garage to a certain degree, but it is mostly only effective for rodents that are looking for an easy way in. Most of the time, a rubberized or cloth-style threshold sealer is easy work for a sharp-toothed rodent. Rodents will also often find other ways of getting into your house, so you will have to find a way to seal not only any electrical conduit coming into the building, but any vents or crawlspaces as well.