Going to keep this quick and easy.

Bought 4 cans and applied it to various areas of the truck. If you're like me, and live in the salt belt, you'll likely be using the high pressure hose on your truck weekly during the winter months.

Fluid film didn't last a very long in the wheel wells. It was blasted off with ease the first time I washed the truck (2 weeks after applying).

I spoke with FF about this and they said that was normal, even though FF's description states it "will not easily wash off." I was told its best used in areas where salt can accumulate but don't get washed frequently.

I can't just trust FF is working and not wash the areas known to rot out.

Anyway, FF is $12-$15 a can. White lithium grease in the rattle can will hold up all winter with as many car washes as you can throw at it. It's about $2 a can.

After wasting $50, I'll be applying white lithium grease to the inner door seams, tailgate seam, inner / upper / top of wheel well, rockers, etc.

 

State uses calcium chloride and liquid urea on the roads here. The liquid urea is something they just started in the last couple of years. i notice a film on my windshield that washer fluid won't touch now.

 

I've used Fluid Film for a number of years - in the road salt capital of the world. (BTW, I'm only paying about $8 a can.) I would agree that it doesn't hold up very well in areas where direct road spray or power washing cause "high velocity contact." That said, in almost any other areas, I've been very pleased with how well the product holds up and how it prevents / inhibits rust. I should add that my main test case is a 2008 Ford F-550 that hauls a Smith Stainless Steel Salter all winter long. Where we've used FF religiously, it's worked great.

On a related note, Fluid Film is specifically formulated to inhibit rust. Last time I checked, White Lithium Grease was not. That said, even though the WLG might still be present after extended use, I'm not so sure it's actually preventing rust.

Just my 2 cents.

 

I use FF on the seams on the bottom of the doors and the bottom of the tailgate after each wash.
- The Mrs' G6, GM installed what I lovingly call a rust flap. Gm has never figured out how to seal a door to the body, so they use all kinds of stupid flaps of rubber for dirt to accumulate in and sit and rust. Dopes. I clean these out with Tork wipe down towels and apply FF to them as well.

These areas do not see a pressure washer directly, so the fluid film stays on them well.

I do not spray down the wheel wells, they get salt in them during the winter but they get washed. I have some specs of rust on the surface, but this is after 9.5 years and 126K miles.
If covering these is a concern to you, you would be better suited to removing any rust that is there roughing up the surface and having professional undercoating applied to those areas.
- I would rather have the ability to clean them vs taking a chance of something getting behind the undercoating and the body myself. This opinion is built after decades of seeing professional rust coated cars rusting even with the annual inspections. I am sure the technology has changed since the late 70s, but so has vehicle factory painting processes.

 

How about wheel well liners? I've used rattle can bed liner on past trucks, but put Ford liners on my 2014 and very happy with there fit and coverage.

 

I think the liners look great. But it just seems like an opportunity for salt and dirt to get trapped behind there.

 

Even though FF doesn't hold very well, I ended up reapplying it in some areas and putting a coat of white lithium grease on top to hopefully keep it in place.