5/16-18 x 4ft Self-Tapping Trailer Deck Screws, Type F - Durable Drive

In this review the reviewer looks at a 300-piece pack of 5/16-18 x 4' self-tapping trailer deck screws and finds them best suited for contractors, trailer owners and serious DIYers who need a reliable fastener for floorboards and mixed wood-to-metal decks. The single biggest reason to buy is the combination of a Type F thread-cutting point and a Torx T-40 star drive, which together make installation faster and reduce strip-out compared with conventional screws. The pack size and hardened steel finish also make these screws a practical choice for larger jobs where durability matters.

Key Features

• Type F point: Cuts threads cleanly into both wood and thin metal so installers can fasten trailer floorboards without pre-tapping each hole.
• Hardened steel construction: Offers the strength required for heavy-duty use and resists breakage under higher torque during installation.
• Black phosphate and oil coating: Provides added corrosion resistance for outdoor and trailer applications where exposure and wear are common.
• Star drive T-40: Reduces cam-out and allows higher torque transfer, improving longevity of both screw and bit during repetitive work.
• Flat countersunk head: Sits flush with decking and creates a neater finish while preventing catch points on trailer floors.
• 300-piece pack: A bulk quantity that keeps a project moving without repeated trips for replacements.

Who It's For

This product is aimed at professionals and hobbyists who install or repair trailer decks and need a fastener that performs well with both wood and sheet metal. Contractors, automotive repair shops and fabricators will appreciate the hardened steel and thread-forming Type F point for repetitive, durable fastening.

Those who should look elsewhere include users who require stainless steel for marine saltwater exposure or those needing decorative exposed fasteners in a finished furniture project, since the black phosphate finish is functional rather than decorative.

Pros & Cons

Pros

• Excellent thread-forming performance for wood-to-metal decking repairs, cutting threads as advertised.
• Star drive T-40 reduces bit slippage and makes installation faster with powered drivers.
• Hardened steel with black phosphate finish improves resistance to corrosion for trailer use.

Cons

• Not stainless; for extreme saltwater exposure a different material is preferable.

Specifications

Size	5/16-18 x 4 in
Quantity	300 pcs
Point type	Type F self-tapping (thread cutting)
Drive	Star drive (Torx) T-40
Head style	Flat countersunk
Material & finish	Hardened steel, black phosphate and oil coating
Typical uses	Trailer floorboards, wood-to-metal decking, industrial repairs

Our Verdict

These 5/16-18 x 4 in Type F self-tapping screws are a practical, value-oriented choice for trailer deck work and other projects where thread-cutting into wood and thin metal is required. The hardened steel and Torx drive combine to reduce installation frustration and improve longevity, making the 300-piece pack a good buy for professionals and serious DIYers.

Frequently Asked Questions

Can these screws cut threads into steel plate?
Yes; the Type F point is designed to cut threads into thin metal such as plate steel used on many trailer floors, though plate thickness limits should be observed.

Will the star drive prevent stripping?
The Torx T-40 star drive reduces cam-out and slippage, which helps prevent bit and head stripping during higher torque installation.

Are these screws suitable for marine applications?
They have a black phosphate finish for corrosion resistance, but they are not stainless steel; for sustained saltwater exposure choose stainless fasteners.