🚀 go-pugleaf

Does anyone have experience with treating *surface*
rust?  This is not (yet) a structural problem, simply
a dusting scattered over random areas on the underside
of my car.  I'm looking for a treatment or procedure
to stop the spread of the existing stuff, and also
prevent any further rusting.

Some suggestions I've heard are:

(a) spread motor oil on the underside [will this stop existing rust?].  

(b) spray aerosal undercoating mix on the underside [will this eventually
separate from the metal and create a cavity for moisture to collect in?]

(c) spray the underside with commercially available primer paint for 
*rusty* metal, e.g. available from Rustoleum.  [does this stuff really
work?!  If so, which brand is best?]

My primary concerns are (1) effectiveness, (2) ease
of application, and then (3) cost.

I'd welcome all advice you have on the above ideas, and
any other approaches you can suggest.

Thanks in advance.


   Ron Pankiewicz