Fluid Film (Black) Powerful Protection

FLUID FILM BLACK Corrosion Protection & Vehicle Undercoating

Black, Non-Drying Wool-Wax Undercoating for Vehicle Chassis and Metal Corrosion Protection

FLUID FILM BLACK is a black corrosion preventive, penetrant and lubricant designed for automotive undercoating and other metal-protection applications. Its wool-wax-based formulation creates a wet, non-drying barrier that creeps and migrates into seams, crevices and other difficult-to-reach areas.

The coating helps protect metal against moisture, road salt and brine while its black color provides a darker, more uniform appearance on vehicle frames and underbody components. It can also visually cover existing surface rust while the coating penetrates into rust and scale.

FLUID FILM BLACK contains no solvents and remains soft rather than curing into a hard coating.

Key Benefits

• Black vehicle undercoating and corrosion preventive
• Wool-wax and petroleum-oil-based formulation
• Contains no solvents
• Does not dry out or form a hard coating
• Creeps and migrates into seams and tight spaces
• Helps protect metal against road salt and brine
• Displaces water from metal surfaces
• Penetrates rust and corrosion scale
• Helps protect vehicle chassis and underbody components
• Provides lubrication for moving metal parts
• Black finish helps darken chassis components and existing surface rust
• Suitable for most painted surfaces
• Can be used on aluminum without pitting according to manufacturer testing
• Available in aerosol and bulk non-aerosol formulations

Vehicle Undercoating and Rust Protection

FLUID FILM BLACK is particularly useful for vehicle underbody areas exposed to moisture, road salt and winter brine.

Common automotive applications include:

• Frames and chassis
• Frame rails
• Underbody metal
• Inner body seams
• Wheel-well metal surfaces
• Suspension components
• Nuts, bolts and fasteners
• Hitch components
• Steel brake-line exteriors
• Door and body cavities
• Truck beds before installation of compatible liners
• Other exposed metal surfaces

The coating remains active and mobile instead of curing into a rigid film. This allows it to migrate into seams and irregular surfaces where moisture and road salt can collect.

Avoid applying lubricants or corrosion coatings to braking friction surfaces, tires, drive belts or other components where a slippery film could interfere with safe operation.

Protection Against Road Salt and Brine

Road salt and liquid brine accelerate corrosion by introducing moisture and electrolytes to exposed metal.

FLUID FILM BLACK forms a soft barrier that helps isolate the metal surface from these corrosive materials. Its water-displacing properties also help move moisture away from the metal.

Because the coating remains wet and does not harden, vehicle undercoatings should be inspected periodically and reapplied where road spray, abrasion or cleaning has removed the protective film.

Black Finish for Vehicle Chassis

The primary visual difference between FLUID FILM BLACK and standard FLUID FILM is the black coloration.

The black coating is useful where the owner wants corrosion protection while maintaining or restoring a darker appearance on:

• Frames
• Chassis components
• Underbody metal
• Previously rusted areas
• Older vehicle undercarriages

FLUID FILM BLACK does not convert or permanently remove rust. The coating penetrates into existing rust and helps isolate the underlying metal from moisture and oxygen while the black pigment visually darkens the treated area.

Loose rust and flaking material should be removed before application when practical.

FLUID FILM BLACK vs. Original FLUID FILM

Both products use the same general FLUID FILM corrosion-control approach, including wool-wax-based protection, water displacement, penetration and a non-drying film.

FLUID FILM BLACK:

• Black-colored coating
• Particularly suited to automotive chassis and underbody applications
• Helps visually darken existing rust and weathered undercarriage surfaces

Original FLUID FILM:

• Clear to straw-colored appearance
• Better suited where a black coating is not desired

Choose the version based primarily on the desired finished appearance and application.

Does FLUID FILM BLACK Dry or Cure?

No. FLUID FILM BLACK is intentionally designed to remain soft and non-drying.

This allows the coating to continue creeping into seams and metal pores rather than becoming a rigid film.

The non-drying characteristic also means:

• The surface can initially collect some dust
• The coating may transfer when touched
• Areas exposed to heavy road spray or abrasion should be periodically inspected
• The surface must be cleaned before painting

This behavior is normal for the product and is part of its corrosion-control design.

Paint, Rubber, Plastic and Aluminum Compatibility

The Product Data Sheet lists no effect on most painted surfaces and no pitting on aluminum.

For rubber:

• Manufacturer testing lists no effect on neoprene
• Manufacturer testing lists no effect on Buna-N
• Non-oil-resistant rubber may swell

FLUID FILM also advises caution around existing vehicle undercoatings because the product may soften some undercoating materials or undercoating-type paints.

Test a small area first when compatibility is uncertain.

Preparing a FLUID FILM-Treated Surface for Paint

FLUID FILM BLACK contains no silicones, but paint should not be applied directly over the wet coating.

Before repainting, remove the FLUID FILM thoroughly. The manufacturer recommends hot-water or steam detergent washing at approximately 120°F where appropriate.

The surface should be clean, dry and free of residual oil before painting or applying another coating.

Application

For vehicle undercoating, FLUID FILM can be sprayed onto clean accessible metal surfaces and into cavities and seams.

For bulk material, FLUID FILM recommends approximately:

• 70 to 90 PSI for compatible air-powered undercoating guns
• Around 2,000 PSI minimum for airless spraying equipment
• Approximately 3 to 4 mil wet film thickness
• Roughly 250 square feet of coverage per gallon at that film thickness

FLUID FILM is thixotropic, meaning it becomes thicker while sitting. Stirring or agitation returns the material to a more fluid consistency for application.

Application requirements can vary by equipment and package type. Follow the instructions for the specific aerosol or bulk product being used.

Typical Technical Properties

Typical properties are based on manufacturer Product Data and may differ between aerosol and non-aerosol packages. Refer to the current Product Data Sheet and Safety Data Sheet for the exact product being used.

Frequently Asked Questions

What is FLUID FILM BLACK?
FLUID FILM BLACK is a black wool-wax-based corrosion preventive, penetrant and lubricant commonly used as a vehicle undercoating. It remains soft and wet rather than curing into a hard coating.

What is FLUID FILM BLACK used for?
It is commonly used to protect vehicle frames, chassis components, underbody metal, seams, cavities, fasteners and other metal surfaces exposed to moisture, salt and brine.

Is FLUID FILM BLACK good for vehicle undercoating?
Yes. Automotive undercoating is one of the manufacturer's specifically identified applications for FLUID FILM BLACK.

What is the difference between FLUID FILM BLACK and regular FLUID FILM?
The most noticeable difference is color. FLUID FILM BLACK leaves a black coating that can darken a vehicle chassis and visually cover existing surface rust. Original FLUID FILM has a clear to straw-colored appearance.

Does FLUID FILM BLACK stop rust?
FLUID FILM BLACK is designed to penetrate rust and provide a barrier against moisture and oxygen, helping inhibit continued corrosion. It does not chemically convert or permanently remove existing rust.

Can FLUID FILM BLACK be sprayed over rust?
Yes. It can be applied over existing rust, but loose scale, flaking rust and debris should be removed when practical so the product can reach the underlying surface.

Does FLUID FILM BLACK remove rust?
No. FLUID FILM is not a rust remover. It penetrates rust and scale and helps protect the metal beneath it.

Does FLUID FILM BLACK dry?
No. The product contains no solvents and is designed to remain wet and non-drying.

Does FLUID FILM BLACK harden like rubberized undercoating?
No. FLUID FILM BLACK remains a soft, active coating. It does not cure into a hard rubberized shell.

Does FLUID FILM BLACK wash off?
The coating is formulated to resist normal exposure, but heavy road spray, abrasion, detergents and pressure washing can gradually remove it. Inspect treated areas periodically and reapply where the coating has worn away.

How often should FLUID FILM BLACK be reapplied to a vehicle?
Reapplication depends on road conditions, climate, mileage, washing and abrasion. Inspect the underbody periodically, particularly after a winter season, and reapply wherever the film has become thin or has been removed.

Is FLUID FILM BLACK safe on vehicle paint?
The Product Data Sheet lists no adverse effect on most painted surfaces. Compatibility should still be checked on an inconspicuous area, particularly with specialty coatings or aftermarket undercoatings.

Is FLUID FILM BLACK safe on rubber?
Manufacturer testing lists no effect on neoprene and Buna-N, but FLUID FILM may cause swelling in non-oil-resistant rubber materials.

Is FLUID FILM BLACK safe on plastic?
FLUID FILM states that its products do not adversely affect plastics. Compatibility testing is still appropriate for unusual or specialty materials.

Can FLUID FILM BLACK be used on aluminum?
Yes. The Product Data Sheet reports no pitting on aluminum under its test conditions.

Can I paint over FLUID FILM BLACK?
Not directly. The wet coating must first be thoroughly removed. The manufacturer recommends hot-water or steam detergent washing before repainting.

Does FLUID FILM BLACK contain solvents?
No. FLUID FILM BLACK is formulated without solvents.

How much FLUID FILM is needed to undercoat a vehicle?
The manufacturer's automotive guidance indicates that approximately one gallon can cover a vehicle, although actual use depends on vehicle size, coating thickness and how extensively cavities and underbody components are treated.

Can FLUID FILM BLACK be used with an undercoating spray gun?
Yes. Bulk FLUID FILM can be applied using compatible undercoating equipment. Manufacturer guidance lists approximately 70 to 90 PSI for compatible air-powered undercoating guns.

Does FLUID FILM BLACK protect against road salt?
Yes. Protection against salts and brines is one of the specifically identified automotive uses of FLUID FILM BLACK.