Hello all,
I have been reading and reading and reading on undercoating and am still not 100% sure what I want to use. I know for the insides of the doors and rocker panels I will use 3M Rust Fighter-I, and have been thinking of using it on the entire underbody but I know that POR-15 is supposed to be good stuff as well. It does not trap moisture and is a paint rather than a rubberized coating (Which I dont want). I know that most people say that oil is the best so I am debating using the 3M Rust Fighter which is an oil that becomes "tacky" for the rest of its existance, POR-15, or Husquarvarna Bar Oil...

Thanks for your input.

I also bought the 3M spray gun and interior panel nozzle attachment. Couldn't beat it for $65 shipped for both with the current 25% off pricing...

 

Wait... Why don't you want a rubberized coating? I'm all ready to have the Line-X shop spray a DuPont undercoat on my truck. Although I'm just in it for the sound deadining.

 

I used POR-15 on my last one, lasted for ever.

 

im not sure exactly what product it is, but in MI we can get an actuall grease undercoating. lasts forever.... makes a drippy mess in the summer time for a year or two.. but well worth it.

 

Because it tends to trap moisture. Trapped it on the underside of my F-150 and it rusted clean through the bottom of the bed.

 

I had seen you post about this previously.... Do you have any pics? The only thing swaying me away is that the 3M stuff makes less of a mess. Do they spray the whole underside or what?

 

yes, they spray all the underbody sheet metal, frame etc. inside the tailgate, bottom inside edge of tailgate(usually rusts out on all trucks). hood (not ours because alum.) inside of doors halfway up. in the front door jamb/sill they actually drill a 3/8" hole in each side so they can spray the inside of the front fender well that is impossible to get otherwise. then it is finished off with a factory style grommet. no one has ever noticed that it wasnt factory on any of my cars.....

 

I would love to see some pictures. Do you know if they have examples there that you can take a look at? Just want to see what it will look like before I let someone drill holes in my $45k truck. I am also concerned with the components inside of the door being covered with grease such as speakers, etc. How much grease do they pump into the doors?

 

Where are they located in Michigan that does this?

 

There is a local guy around here that does the grease coat. Been doing it for many, many years. It is good stuff if you want to prevent rust. The vehicles he does do seem to last forever. But there is a big catch. It is "extremely" messy. Most shops will charge you extra or even refuse to work on your vehicle if you have it coated with his stuff. It will also drip for a very long time. So plan on parking in the yard or you will have a big mess in your driveway for many months. It really never dries but does stop dripping after a time. Until you go and have it touched up.