It's funny, but Vaseline, grease and oils shouldn't be used to repel squirrels. It gets on their fur (and ingested) and they can't get it off. In the winter it will cause them to freeze because their fur can't trap their own body heat. It also makes them more vulnerable to predators.
Mix in a tablespoon of cayenne pepper to 10 pounds of bird seed and the squirrels will leave it alone, guaranteed. Birds are not bothered in the least by cayenne, but mammals, like squirrels, most definitely are.
I got that tip from one of the biologists at the Nature Center at Land Between the Lakes. It's what they use at the Center. They have separate feeders for birds and squirrels, and it keeps the squirrels out of the bird seed. We have a couple of bird feeders at the house (plus hummingbird feeders in the summer) and the squirrels don't bother the feeders at all. And we have a lot of squirrels. A really lot. But we have oak trees that produce a lot of acorns.