What rust protector should I use under my car?

[myasylum]

My car is a California car, but it was sitting in the grass in Wisconsin for 2 years so the under body is starting some issues. All the rust is just surface rust, so over all it's still in good shape. Still, is there anything you suggest that I can use to stop the surface rust from getting worse? A simple spray or undercoating?

Thanks!

 

[64dart170]

Well, I have a couple of sugestions but first you have to decide, are you going to full restore underside, partial, just wanting to help it for a year or so???
Just like anywhere else on the car you could start by wire wheel then go through the whole refinish process and top off with undercoating.
If you want a temp halt you can pressure wash or run through car wash to clean heavy dirt or mud. Then coat the underside, everything rust & metal with wd-40 then coat the undercoating with a tire cleaning foam. This is also a quick way to detail your daily driver! You should do your wheel wells every time you foam your tires anyway it looks better.
You can also use a rust converter spray. My $.02! Good Luck, I'm sure there will be better ideas than mine but I'm cheap, country daily driver!