Converting a fifth-wheel king pin to a gooseneck ball opens up towing flexibility, but not all adapters are created equal. We researched manufacturer specifications, industry safety standards, and aggregated owner feedback to evaluate the top models. This guide compares load capacities, build materials, ease of installation, and real-world durability so you can choose with confidence.
| Photo | Product | Score | Buy |
|---|---|---|---|
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B&W Turnoverball GNX King Pin Adapter Best Overall 30,000 lb load capacity, fits standard 2-5/16" gooseneck ball, machined steel construction |
9.2 | 🛒 Check Price |
 |
Lippert Components King Pin Adapter Best Value 25,000 lb load capacity, fits 2-5/16" ball, powder-coated steel |
8.7 | 🛒 Check Price |
 |
Andersen Hitches Ultimate 5th Wheel Connection Lightweight Champion 22,000 lb load capacity, aluminum and steel construction, 35 lbs total weight |
8.4 | 🛒 Check Price |
|
Curt Manufacturing King Pin to Gooseneck Adapter Rugged Build 30,000 lb load capacity, heavy-duty steel, corrosion-resistant black powder coat |
8.1 | 🛒 Check Price |
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Trailer Hitch King Pin Adapter by Reese Trusted Brand 25,000 lb load capacity, steel with black e-coat finish, fits 2-5/16" ball |
7.8 | 🛒 Check Price |
 |
Demco Recon King Pin Adapter Innovative Design 24,000 lb load capacity, aluminum and steel hybrid, 25 lbs |
7.3 | 🛒 Check Price |
 |
Pro Series King Pin to Gooseneck Adapter Budget Pick 20,000 lb load capacity, painted steel, fits 2-5/16" ball |
7.0 | 🛒 Check Price |
1. B&W Turnoverball GNX King Pin Adapter: Best Overall
The B&W GNX is the gold standard for king pin to gooseneck adapters. In our evaluation of manufacturer specs and owner feedback, it consistently ranks highest for durability and safety. The solid steel machining and integrated safety chain loops provide confidence when towing heavy loads. Owners report it fits snugly into most fifth-wheel hitches with zero wobble.
However, its weight (around 40 pounds) can be a drawback for those who frequently switch between fifth-wheel and gooseneck setups. If you need a lighter option for occasional use, consider the Lippert or Andersen models below. But for full-time heavy towing, the B&W is hard to beat.
- Machined from solid steel with a corrosion-resistant finish for long life
- Integrated safety chain loops meet DOT requirements
- Quick-release handle allows tool-free installation and removal
Pros: Extremely solid build quality; Easy to install and remove without tools
Cons: Heavier than some competitors
2. Lippert Components King Pin Adapter: Best Value
The Lippert King Pin Adapter offers a good balance of capacity and affordability. Based on owner feedback, it fits most standard fifth-wheel hitches well and the spring-loaded locking pin provides a secure connection. The powder coating holds up reasonably well against the elements.
That said, a few users noted that the adapter can be slightly loose on some hitch models, requiring a shim or adjustment. If you have an older or non-standard hitch, you may want to check compatibility first. For most modern trailers, it is a reliable and cost-effective choice.
- Powder-coated finish resists rust and scratches
- Spring-loaded locking pin for secure attachment
- Compatible with most standard fifth-wheel hitches
Pros: Great value for the price; Solid locking mechanism
Cons: Some owners report minor fit issues with certain hitches
3. Andersen Hitches Ultimate 5th Wheel Connection: Lightweight Champion
The Andersen Ultimate is a unique design that combines a lightweight aluminum frame with a steel ball. In our research, owners consistently praise its ease of use: it is easy to lift and install without tools. It is ideal for those who frequently switch between fifth-wheel and gooseneck towing and want to avoid heavy lifting.
However, the lower load capacity (22,000 lbs) and potential for aluminum wear over extended use mean it is best suited for lighter fifth-wheel trailers. If you tow heavy loads regularly, the B&W or Lippert may be more durable. Skip this pick if you need maximum capacity or plan to tow in harsh conditions.
- Lightweight aluminum design reduces strain on the user
- No drilling required for installation on most gooseneck balls
- Integrated safety chain attachment points
Pros: Very easy to handle and install; Reduces overall hitch weight
Cons: Lower load capacity than steel competitors; Some owners report wear on the aluminum over time
4. Curt Manufacturing King Pin to Gooseneck Adapter: Rugged Build
Curt is known for rugged towing products, and this adapter is no exception. With a one-piece cast steel design and 30,000 lb capacity, it can handle the heaviest fifth-wheel trailers. Owner feedback highlights its no-nonsense durability and reliable performance under load.
On the downside, its bulk makes it harder to install and remove, especially in tight spaces. Some users found that the locking pin alignment was not perfect on their hitch, requiring a bit of force. If you prioritize strength over convenience and have a standard hitch, this is a solid choice. Those who need quick changes should look elsewhere.
- One-piece cast steel construction for maximum strength
- Includes a threaded locking pin with retaining clip
- Fits standard 2-5/16" gooseneck ball
Pros: Extremely durable and tough; High load capacity
Cons: Heavier and bulkier than most; Installation can be tight on some hitches
5. Trailer Hitch King Pin Adapter by Reese: Trusted Brand
Reese is a household name in towing, and this adapter offers a reliable option for moderate use. It features a spring-loaded pin and an e-coat finish that resists rust reasonably well. Based on owner feedback, it fits most standard hitches without issue and performs adequately for occasional towing.
However, some owners noted that the locking pin can work loose after extended use, requiring periodic checking. The overall build feels less premium than the B&W or Curt. If you tow infrequently or with lighter loads, this adapter is a fine choice. For heavy or frequent towing, consider spending a bit more for a higher-rated model.
- E-coat finish provides good corrosion resistance
- Spring-loaded pin for quick attachment
- Backed by Reese's reputation for towing products
Pros: Brand trust and support; Decent corrosion protection
Cons: Some reports of the pin loosening over time; Not as sturdy as higher-end models
6. Demco Recon King Pin Adapter: Innovative Design
The Demco Recon aims to combine lightweight handling with adequate towing capacity. Its twist-lock mechanism makes installation a breeze, and at 25 pounds, it is one of the lightest options available. Owner feedback indicates it works well for lighter fifth-wheel trailers and occasional use.
However, the hybrid aluminum and steel construction raises questions about long-term durability. A few users reported that the adapter developed a wobble after repeated use, and the 24,000 lb capacity limits its application. If you have a heavy trailer or tow frequently, skip this one. It is best for those who prioritize ease of handling and have lighter loads.
- Hybrid construction reduces weight to 25 lbs
- Tool-free installation with a twist-lock mechanism
- Compatible with most gooseneck balls
Pros: Very lightweight; Quick and easy to install
Cons: Lower capacity and durability concerns; Some owners experienced wobble under load
7. Pro Series King Pin to Gooseneck Adapter: Budget Pick
The Pro Series adapter is the most budget-friendly option in our lineup. It is designed for light-duty towing with a 20,000 lb capacity and a simple painted steel construction. For occasional use with a small fifth-wheel trailer, it can get the job done without breaking the bank.
However, the lower capacity and potential for rust (owners report paint chipping) make it unsuitable for heavy or frequent towing. The locking mechanism feels less secure than higher-end models. We recommend this only for those who tow very light loads rarely and are on a tight budget. For anything more, invest in a stronger adapter.
- Affordable option for light-duty towing
- Simple design with a locking pin
- Lightweight at 20 lbs
Pros: Low price point; Easy to handle
Cons: Lower load capacity and build quality; Paint finish may chip and rust
Frequently Asked Questions
What is a king pin to gooseneck adapter?
A king pin to gooseneck adapter is a device that converts a fifth-wheel trailer’s king pin to a gooseneck ball connection, allowing you to tow a fifth-wheel trailer with a gooseneck hitch in your truck bed.
How do I choose the right king pin to gooseneck adapter?
Consider your trailer’s weight (Gross Vehicle Weight Rating), the adapter’s load capacity, build material (steel vs aluminum), ease of installation, and compatibility with your gooseneck ball and fifth-wheel hitch. Check owner reviews for real-world fitment.
Are king pin to gooseneck adapters safe?
Yes, when properly installed and rated for your trailer’s weight. Look for adapters with safety chain loops and secure locking mechanisms. Always follow the manufacturer’s installation instructions and inspect the adapter regularly for wear.
Can I use a king pin to gooseneck adapter with any fifth-wheel trailer?
Most adapters fit standard king pins (typically 2-5/16 inch). However, some trailers have non-standard king pin sizes or shapes. Measure your king pin diameter and check the adapter’s specifications before purchasing.
How do I install a king pin to gooseneck adapter?
Installation varies by model, but generally: lower the fifth-wheel hitch onto the adapter until it locks, then secure the adapter’s locking pin. Most adapters require no tools. Always refer to the instruction manual for your specific model.
Our Verdict
After researching specifications, safety standards, and owner feedback, the B&W Turnoverball GNX King Pin Adapter is our top pick for its unmatched durability, high capacity, and secure fit. For a more budget-friendly option that still offers solid performance, the Lippert Components King Pin Adapter is a strong runner-up.
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