Find the right king pin hitch for goosenecks to tow with a 5th-wheel hitch. This guide highlights five popular adapters and converters, suitable for different trailer setups and vehicles. The selections are ideal for buyers seeking a bolt-on upgrade, heavy-duty towing, or simple conversion without full hitch installation. Each option is explained with who it’s best for, plus a practical limitation to consider before you buy.
| Product | Best For |
|---|---|
| A-Premium Gooseneck Ball Adapter Hitch | Tractor-trailer fifth wheels needing a reliable OE-like fit |
| FlexHitch 30K GTW Gooseneck To 5th Wheel Adapter | Hobbyists or commercial users needing a quick conversion |
| GEN-Y Hitch 3/4″ Gooseneck Coupler Pin | GEN-Y couplers and secure pin systems |
| Gooseneck To 5th Wheel Adapter / Pop-Up | Versatile retrofits for mixed trailer fleets |
| ELSOON WA15 5050 King Pin | Heavy-duty towing with forged steel reliability |
A-Premium Gooseneck Ball Adapter Hitch
The A-Premium adapter fits tractor-trailer fifth wheels with a 2″ king pin interface. It is designed for heavy-duty use and tested to meet OE standards. This option is best for buyers who want a direct replacement that matches factory specifications and requires careful alignment with the fifth wheel plate to prevent tilting. A caution: you may need to lock or block the fifth wheel plate to maintain a level travel path.
- Best for: Users seeking a precise, OE-like fit for gooseneck to fifth-wheel towing.
- Limitation: Requires accurate fifth-wheel alignment and possible plate locking.
FlexHitch 30K GTW Gooseneck To 5th Wheel Adapter
This adapter converts a 4″ round gooseneck tube to a 2″ kingpin interface, letting a standard 5th-wheel hitch tow with no full hitch install. It features a heavy-duty carbon steel design and is rated up to 30,000 lbs GTW with 4,500 lbs tongue weight. The bolt-on approach makes it appealing for at-home upgrades. Best for owners who want a cost-saving, quick-install solution; avoid if your trailer’s tube or original hardware requires welding or specialized fabrication.
- Best for: Truck owners who want a hassle-free upgrade without a full hitch system.
- Limitation: Not a full hitch system replacement; relies on existing 5th-wheel hitch for operation.
FlexHitch 30K GTW Gooseneck To 5th Wheel Adapter (Second Listing)
This listing mirrors the same concept: converting a 4″ round gooseneck tube to a 2″ kingpin interface with a 30,000 lbs GTW rating. It emphasizes easy bolt-on installation and a robust carbon steel build for reliable towing. Best for buyers who want a similar heavy-duty conversion with straightforward at-home installation; choose this if you prefer consistency across multiple trailers, but verify compatibility with your exact gooseneck tube diameter.
- Best for: Reliable, heavy-duty conversions with simple installation.
- Limitation: Similar to the first FlexHitch option; confirm tube compatibility before purchase.
GEN-Y Hitch 3/4″ Gooseneck Coupler Pin
The GEN-Y Coupler Pin is a 3/4″ x 5.25″ usable length pin with a self-locking twist clip included for extra security. It’s designed specifically for GEN-Y gooseneck couplers, making it a targeted fit for users who already own GEN-Y components or want a robust pin system. Best for: GEN-Y owners seeking a secure, simple pin upgrade. Limitation: Not a universal adapter; compatibility depends on using GEN-Y couplers.
- Best for: Secure fit with GEN-Y gooseneck systems.
- Limitation: Limited to GEN-Y couplers; may not fit other brands without adapters.
Gooseneck To 5th Wheel Adapter / Pop-Up Gooseneck
This pop-up style adapter converts a 4″ gooseneck tube to a 5th-wheel compatible interface. It’s designed for semi-tractor or pickup setups with fourth-to-fifth wheel switching in mind. Best for fleets that require occasional switching between gooseneck and fifth-wheel towing. A limitation: the pop-up mechanism may require attention to alignment during operation to maintain stability.
- Best for: Flexible fleets needing mixed trailer compatibility.
- Limitation: Pop-up mechanism may need regular maintenance or adjustment for stability.
ELSOON WA15 5050 King Pin
The ELSOON WA15 5050 forged steel king pin features a 2″ collar and 3/8″ bolster plate. It’s designed to boost towing stability and load capacity for 5th-wheel trailers. Best for buyers seeking a forged steel option with durable construction for heavy-duty applications. Limitation: Specific compatibility is tied to WA15 interfaces; verify fit for your trailer model before purchase.
- Best for: Forged steel construction and high durability.
- Limitation: Compatibility depends on WA15 system and mounting specifics.
Buying Guide: Key Considerations For King Pin Hitches And Gooseneck Adapters
What should you consider before buying a gooseneck-to-5th-wheel adapter?
- Trailer compatibility: Check tube diameter (commonly 4″) and the king pin interface (2″ standard). Ensure the adapter matches your trailer’s neck and your 5th-wheel hitch.
- Weight rating: Verify Gross Vehicle Weight (GTW) and tongue weight ratings align with your load and intended cargo.
- Installation approach: Decide between bolt-on adapters and full hitch replacements. Bolt-on options can be quicker, but may rely on existing hitch components.
- Material and build: Forged steel and carbon steel with corrosion protection offer durability in harsh conditions. Consider the environment you tow in (coastal, winter, off-road).
- Safety features: Look for secure pins, locking clips, and stable alignment mechanisms to prevent tilting or wobble during transit.
- Maintenance: Some pop-up or adjustable designs require regular checks to ensure proper engagement and alignment.
How To Choose: Quick Decision Steps
1) Identify your trailer’s neck size and the king pin size you need. 2) Decide if you want a full hitch replacement or a bolt-on adapter. 3) Compare GTW and tongue weight to your typical loads. 4) Confirm compatibility with your existing hitch system and couplers. 5) Consider ease of installation, maintenance, and long-term reliability.
Frequently Asked Questions
- What is a gooseneck to 5th wheel adapter?
- Do I need professional installation for these adapters?
- Can I use any king pin with any gooseneck?
- Are forged steel pins more durable than standard steel?
- What are common limitations of gooseneck adapters?
- How do I know if a product is best for my load?
A device that converts a gooseneck trailer’s coupling to work with a standard 5th-wheel hitch, enabling towing with a different hitch system.
Most bolt-on adapters are designed for at-home installation with basic hand tools. Some setups may benefit from professional inspection, especially for critical loads.
Not all king pins are universal. Confirm the interface (2″ standard) and the tube size (commonly 4″ round) match your trailer’s neck and hitch.
Forged steel generally offers higher strength and fatigue resistance, making it suitable for heavy-duty towing and long-term use.
Limitations include compatibility with specific couplers, potential alignment needs, and the added point of failure in conversion systems.
Match the GTW rating, tongue weight, and trailer neck dimensions to your typical loads and trailer type. Choose a model with proven stability features for your environment.