I live in southeast Michigan, where road salt is used VERY liberally in the winter, so cars around here tend to rust pretty badly. Here is a shot I just took of the inside hatch of my wife's Taurus X (4 years old, 60k miles):


Needless to say I'm pretty paranoid about rust. I took delivery of my 2011 F-150 Lariat Ecoboost one year ago tomorrow, and it has just under 12k miles on it. It is washed regularly with underside flush, and is waxed 3-4 times in the summer. I want this truck to last me 10+ years, and I firmly believe that rust will be the #1 issue I'll have long-term.

So, last night I was changing my oil and I looked around under the truck. First I saw this on the transmission crossmember:


Not a lot, but again, this truck is one year old. Looking at the rocker panels, I saw this:




There are a series of 40mm access holes on the inside of the rockers, and they are covered with tape. Yes, tape. The front-most one on the passengers side had already fallen off, and the others are well on their way. This will allow all kinds of dirt, salt, and moisture to get up inside the rockers.

Now, I'm not happy that they apparently cheaped out on such an important area on a truck that stickered at $47k, but that's water under the bridge at this point. I want to do everything I can to fix this and prevent future rust. Here's my plan:

1. Powerwash the ever-loving crap out of the bottom of my truck and let it dry for a couple of days.
2. Hit the existing rust spots (like the crossmember) with POR-15.
3. Remove all the tape and spray Waxoyl 120-4 inside the rockers and any other enclosed areas I can reach. Also spray the bottoms of the doors and tailgate with the stuff.
4. Find and install some kind of more substantial plugs in the holes, hopefully something plastic or rubber.
5. Spray the rest of the underbody with Waxoyl Hardwax. (Same link, scroll down a bit).
6. Repeat once a year.

Thoughts? Would you do it differently? If so, how?

 

Fluid Film is another option. Do a search if your not familiar with it. I'll be coating my 2013 with it as soon as I take receive it.

 

Hmm, it's quite a bit cheaper than Waxoyl, too. Thanks!

 

I think you are better off keeping the drain holes such as the one right below the circle in your last picture open than you are plugging things off.

 

Agreed, I wasn't planning on trying to plug those, just the big round holes above. After all, the factory did "plug" them by putting tape on. I just want to do what they did, only better.

 

You should take it to a shop that specializes in rust proofing. A professional place should wash the entire vehicle, put it on a lift, pressure wash the bottom, and finally dry the vehicle with hot air before applying the oil. They also drill small holes in the doors so they can apply the oil inside where rust often starts. If you have a bedliner, take it off and tell them to spray the bed as well.

Ideally the treatment should be repeated annually and applied in the warm summer months, as this helps the oil penetrate better. Afterwards leave the truck parked on the street for excess oil to drip off and wait a few days before you wash the vehicle.

 

Fluid Film and an undercoating gun and you won't have any rust problems....the stuff works incredible.

 

why not just have the dealer undercoat and rust proof it?

back home there was a local company that did it as well (Zebart) but my brother used to apply the stuff at one of the local ford dealers.

eastern iowa was the same, the only thing they use is salt, and that hits the road 2hrs before an expected event, especiall on bridges (i think it was mag-chloride on bridges, which is WAAAY worse than salt).

that always worked well for us. the undercoating is a ruberized asphalt product which covers all exposed steel (except drivetrain parts) and then they sprayed a yellowish goup in all the holes in all the panels, including the stake pockets.

all of mom and dad's got a Zebart appointment ... must have been worth it because my dad can pinch a penny hard enough to make abe lincoln fart ... he woudlnt do it if it was not shown to him that it was worth it in the long run. come to think of it ... mom and dad's cars always looked good when the sold them.

used to cost about 400 bucks. i got mine done for 40 bucks and a case of beer
that's what i'd do......

 

It was the same way around here when I was growing up, there was a Ziebart in every town and it was the only way to keep a car from rusting out in a couple of years. But nowadays, they are a lot harder to find, and looking at their website, it seems like they concentrate more on detailing than rustproofing. Could still be worth a phone call, I suppose. There is a Canadian chain called Krown that looks decent, and I live close enough to make it doable.

My concern with any "professional" application is that it's only as good as the person doing it. I know I'll take my time and do it right with my own truck, but will the minimum-wage kid at the shop who has 5 more vehicles to do that day do the same? I'm also not a fan of rubberized undercoating, yes it cuts down on noise, but eventually it flakes and separates, and creates pockets that can trap moisture. That's why I'd prefer to go with the wax/oil based systems and just do it once a year.

 

Ziebart is not worth it IMO. We had it done on the Expedition and it traps more water and crap than it keeps off.

 

I live in NE Ohio, so I'm concerned also...
How much "Fluid Film" will be needed to coat the bottom of the truck?

Automobile Undercoating

 

I bought a gallon last year for my F350 Crew Cab 8' box that I owned at the time. I think I could have gotten 4 application on that vehicle with the gallon. I borrowed a spray gun from our shop at work hooked up to my air compressor at home. Application was easy.

 

i have used fluid film for quite a long time...spraying every crevice i can find....inside the bottom of the doors,tailgate,inside the rockers..(just put some new tape on there)...
the stuff is great.....
when i purchased my 99 150 new,i started out with liquid wrench ,which worked pretty well...until i found fluid film.....there was no rust in the rockers or anywhere else.....i swear by the stuff..

and i worked at a rustproofing place many years ago and i would never use any of it except texaco cosmoline.......hard to find and it is applied like fluid film.....but way heavier and a lot more messy.....

there is a place in south lyon,,walled lake , livonia and pincney that sells fluid film......
if you cant find the dealer locater let me know.....

 

Thanks, folks. For those of you who've worked with Fluid Film, how thick is it? I'm wondering if I need their sprayer to apply it or if I can do it with something like a garden sprayer?

 

I think you'll need more pressure. It's thinner than honey, but not much.
Also, you don't need to put it on thick. A thin layer is fine as it creeps and crawls into areas you missed. I've seen it gradually spread several inches (a very thin film) if left alone in warmer temps. I use the aerosol cans to spray in the doors and tailgate areas because they create a fog along with the spray, and everything inside those areas gets a protective film. I love the stuff. As the Frank's Red Hot sauce commercial says, "I put that $#!+ on everything".