Chevy & GMC Vans

Howdy...hopefully I'll be getting my astro soon, and I want to rustproof (as much as possible) underneath when i get it. I know to wire brush first, but what materials do you people recommend to "rustproof" and seal the underneath? Thanks in advance.

I own a 2001 safari cargo van and I can say I rust proofed the bottom of the van myself with this FORMULA 2000 ( $11.99 ) a spray ( black / silver can ) that works very well for me ...from CANADIAN TIRE.... It stops the rust in it's tracks it stays moist and lasts up to 7 years with touch ups... Two or 3 cans it took to do all the underside , doors and wheel wells ....I have tried a few products but this one works best...

Best one? Move to an area where salt is NOT used on the roads.

I use penetrol. It's an oil paint additive. It penetrates rust and stops the oxidation. You can put it directly over heavy scale-no scraping. Simply re-apply the heavy scaled areas as the heavy stuff will slough off by itself. I use my HVLP paint sprayer. Being a painter and having the stuff laying around helps but do yourself a favor and read up on this stuff on line it's pretty amazing and cheap!

Using the penetrol, do you spray it on by itself, or do you have to mix it with a paint ???

The absolutely best stuff I have found after there is light rust, is Fluid Film. It goes on wet, almost waxy and stays that way forever. It is very hard to wash off and creates a moisture barrier and works as an awesome lubricant.