Those that use wool wax or fluid film ?
- Thread starter Colvin
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My plan this year is to spray it early and before the salt hits check for any areas that have washed off or need extra attention. I try not to be stingy but there are so many areas to try to hit under my truck.
I don't use FF or WW, there are better choices imo, which I'd rather not debate/hijack in this thread. My reasoning for seeking a better product is: if I'm going to do this time consuming job I'd rather use a better product. Having said that I pay special attention to areas that water can enter that can't be seen. Inner cavities, inside doors, rocker panels, inner frame rails, fenders, pillars, etc. etc. I use a rustproofing gun with wands for all of that, then coat the undercarriage with my airless sprayer. I touch up as needed, during oil changes, tire rotations, and inspect and re-coat if needed in the fall. So far so good.
Kestas
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One mistake I've made is not covering all the way around fuel lines and brake lines. Simple spraying will leave a shadow of uncovered line that will rust with time.
Door inner cavities are important. So are frame rails and the back side of any finished panel.
Door inner cavities are important. So are frame rails and the back side of any finished panel.
Look for anything the factory undercoaters missed. Do the rail area under the doors. Certain cars rust there. If there are any drain holes in the rail area, put a straw nozzle in there and spray. On GM trucks spray the front sway bar mounts. I also spray bolt/nut combos that might have to come apart for component replacement. On older trucks without plastic liners clean the wheel arch lip, let dry and spray the inside of the lip. Try get spray just ahead of the front wheels, low inside the fender.
The bottom of the vehicle will wash off over time. I don't get too paranoid about it. I make sure I get a good coating on the brake and fuel lines when I'm undereath. On the Caravan, I drop the spare tire and coat everything there including the cable.
I've been FF'ing the Caravan since I got it in 2015. Inside the door panels and quarter panels the FF sticks and doesn't drip down. I still do it yearly, but I don't need as much now inside the doors.
One area I pay more attention to is to remove the front wheels and remove the plastic wheel liners. I make sure to get a good coating on everything including the front part of the quarter panels where the salt and slush can easily penetrate. On the Civic the holes that support the push pins have rusted larger. Previously Rust Check or Krown did not pay good attention to those areas IMO.
Every second year or so I remove the inner door panels and roll the windows down so I can coat the inside of the doors from the top to the bottom. My wand on the gun is plastic so it doesn't do the best job to get the FF to the top of the inner panels. I'm not going to drill multiple holes on the door sills to get better access.
I used some fluid film gel (Fluid Film BN gel i think) on the metal piping underneath the car that go to the diesel heater.
They had some rust on them - now after a year they are in quiet good condition, some areas have been weakened with surface rust visible. But that was to be expected when the lines are underneath the car and get salt spray in winter. But the Fluid Film BN did a good job.
I also coated my jack points at the frame rail since they are prone to rusting. They still look good. Fluid Film spray used behind the wheel arch plastic needs to be topped up regularly.
They had some rust on them - now after a year they are in quiet good condition, some areas have been weakened with surface rust visible. But that was to be expected when the lines are underneath the car and get salt spray in winter. But the Fluid Film BN did a good job.
I also coated my jack points at the frame rail since they are prone to rusting. They still look good. Fluid Film spray used behind the wheel arch plastic needs to be topped up regularly.
Just a tip for truck owners. As we all know it has been down right shameful how trucks have rusted along the rear wheel wells. If you purchased a new truck lately it probably has plastic liners. However, have a close look. Some of those models have small holes in the plastic in two or three positions along the wheel arch. I would get the nozzle in those holes and spray along the wheel arch if possible. Good luck. If you are only keeping the truck for 10 years or less, no big deal. If you expect 300,000 miles and 20 years, spray now. 
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I use flex seal...the upside is that my truck floats in high water
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I'll spray basically everything but the exhaust, the exhaust hangers and rubber suspension components. I'll also avoid any body molding rubber underneath at he seams.
I like FF but it doesn't stay longer than a few months in a high exposure areas. Cosmoline (not sure I spelled that right) is better for that stuff.
I like FF but it doesn't stay longer than a few months in a high exposure areas. Cosmoline (not sure I spelled that right) is better for that stuff.
JTK
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Unless the product wears like iron, it's going to get blasted off in areas that are subjected to road spray.
You can spray any and all areas under the vehicle with FF or WW. It's safe on electrical connections and I know it says on the cans it can swell rubber components. I've never experienced that, but I believe others here have seen it. I don't know how much 100% rubber is on a vehicle these days. If so, about any grease , oil or contamination would ruin it.
These products are relatively inexpensive, easy to apply, don't drip, easy cleanup and you can do a decent job on a standard vehicle in under an hour. Woolwax even smells nice (fluid film not so much).
You can certainly spend a ton more money, time and mess on other products which will give you the ability to do the job without yearly re-sprays. There's gives and takes to everything.
You can spray any and all areas under the vehicle with FF or WW. It's safe on electrical connections and I know it says on the cans it can swell rubber components. I've never experienced that, but I believe others here have seen it. I don't know how much 100% rubber is on a vehicle these days. If so, about any grease , oil or contamination would ruin it.
These products are relatively inexpensive, easy to apply, don't drip, easy cleanup and you can do a decent job on a standard vehicle in under an hour. Woolwax even smells nice (fluid film not so much).
You can certainly spend a ton more money, time and mess on other products which will give you the ability to do the job without yearly re-sprays. There's gives and takes to everything.
I use FF on my F150 and have had good results. I focus on the rear frame rails and under the bed but the entire frame gets treated.
Front frame section, control arms and on top of the strut towers.
Front frame section, control arms and on top of the strut towers.
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Deterioration of rubber always seems to be a problem. Another problem I had the past couple years was the back doors of my 83 Caprice filling with water because the drain hole became clogged with undercoating, from years of applications.
My frame and undercarriage is like brand new but my body is starting to rust in places. So I feel I spent too much time on the under carriage and not enough getting inside all panels. The car is 37 years old and the original paint is shot however.
Also if I had the extra money right now I'd be using cosmoline on the undercarriage/high wash areas and fluid film or other light products on the hidden areas.
My frame and undercarriage is like brand new but my body is starting to rust in places. So I feel I spent too much time on the under carriage and not enough getting inside all panels. The car is 37 years old and the original paint is shot however.
Also if I had the extra money right now I'd be using cosmoline on the undercarriage/high wash areas and fluid film or other light products on the hidden areas.
I use Fluid Film on all my vehicles. I brush the product on as I have not tried spraying it yet. The product lasts about 6 months in areas that get extremely wet. The rest is much longer. They get treated at least once a year. When I rotate the tires I spot treat those areas.
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I’d like to buy some cosmoline too, I used it probably ten years ago on a truck I owned and it really sticks good...long term, wax like film. A lot more durable than the fluid film. Fluid film I think is good for the inside of frames, inside of rockers and doors, but it really doesn’t “stick” under a vehicle for very long. It just washes away. And I use the stuff twice a year...application after application. And that does “help”, applying it over and over again. Running it over a dusty road after, letting it build up in layers, but it takes years of multiple applications to do what cosmoline can do in one application.
Do some searching for problem areas on your vehicle. Mine is an F150 which are known for rocker rot especially but also fender well lip rust. Therefore I make sure to use a wand and spray those areas well.
Can anyone identify what year this Ram is? Even though it had the plastic liner in the rear wheel wells, it still rusted. I would have the wheel wells done on any pickup if you plan keeping it for more than 10 years, in rust prone geographical areas.
Man, I'm glad I don't live in the rust belt.
That's the way most Rams around 08 (that body style) look around here. I have 2 friends that have a 14 ram and a 15 power wagon. Both babied and krown oil sprayed yearly and both needed a new fender just before the warranty on one and just after on the other.
A roommate I had got a new warranty box on his 14. Also undercoated yearly according to him. My friend who's a body shop manager says the undercoat doesn't keep them from rusting because of the inner liner. They all rust eventually according to him, although others claim that's not true (including the one friend with the 14 until his rusted through).
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