New cars aren't even undercoated... my 230k mile 2001 truck still has primer on the underide and it's driven year round, mud/gravel, snow/salt etc.
There's no need for either other than the wheel wells and inner quarters unless you want to cover up flaws.
This right here is just frigging hilarious. I've worked from Washington, PA to Philly and all over Ohio the past 20 years. I know what gravel Roads which is Limestone and Salt and Calcium Choride does to your car. I've watched 2 Dodge trucks a Ford and Chevy just Rot away. I've used Undercoating on all my hunting rigs in the past and I love the dirty gray look it leaves when you try and clean it up lol. If I had a trailer queen or live in Miami Beach or Southern Cal I wouldn't use either but I drive my cars. So after reading your hilarious comment I'm done with this post.
