I'd re caulk it as a "better safe than sorry" type thing. I can't hurt. I would think that any flexible outdoor caulking would work. They make some sealants that you can apply directly over the cracks and holes to fill the gaps without peeling the old off, but I don't recall the names offhand. Any RV place should be able to tell you what they use.
2015 Chevy Silverado LTZ - HD tow package
2017 Rockwood 2703WS Emerald Edition