

Bulldog Gooseneck to 5th Wheel Trailer Coupler Adapter 30,000 lbs King Pin Square Inner Tube Only Convert Ball Fifth Wheel Hitch to Gooseneck
Model: 0289650300KING PIN GOOSENECK COUPLER
• Allows gooseneck trailer to be towed with vehicles equipped with a fifth wheel hitch
• Feature dual set bolts
• Round model features exclusive load bearing pin
• Square model features exclusive load bearing pinch bolt
• Available with or without outer tube
About Bulldog
This part is a perfect choice for your Cattle horse Livestock and other trailers made by manufacturers like Big Tex Kaufman PJ ATC Gatormade Anderson Load Trail GN WITZCO Wells Cargo Barret Red Rhino Middlebury Elite Lark Snake River Load N Go and many more
$239 99 $293.75 18% OFF
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Product Details
- Brand: Bulldog
- Model: 0289650300
- UPC: 016118108354
- Includes: Gooseneck to 5th Wheel Coupler Adapter
KING PIN GOOSENECK COUPLER
• Allows gooseneck trailer to be towed with vehicles equipped with a fifth wheel hitch
• Feature dual set bolts
• Round model features exclusive load bearing pin
• Square model features exclusive load bearing pinch bolt
• Available with or without outer tube
About Bulldog
This part is a perfect choice for your Cattle horse Livestock and other trailers made by manufacturers like Big Tex Kaufman PJ ATC Gatormade Anderson Load Trail GN WITZCO Wells Cargo Barret Red Rhino Middlebury Elite Lark Snake River Load N Go and many more
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Bulldog Gooseneck to 5th Wheel Trailer Coupler Adapter 30,000 lbs King Pin Square Inner Tube Only Convert Ball Fifth Wheel Hitch to Gooseneck Install Notes
Installation and Maintenance Instructions for Gooseneck Coupler
Specifications:
- Rated according to SAE J2638 standards.
- Requires a 2 5/16” hitch ball rated equal to or greater than the coupler’s capacity.
- Maximum extension: 8 inches from the fully retracted position.
Tools Required:
- Torque wrench capable of 125 ft-lbs.
- AWS-certified welder (for welding tasks).
Safety Notes:
- Do not exceed the coupler, hitch, vehicle, ball, or trailer weight ratings, including the load.
- Never position any body part under the product or the load it supports.
- Secure the load, vehicle, and trailer by blocking wheels before latching or unlatching the coupler.
- Inspect all components for signs of wear or damage before towing.
- Replace bent, broken, or worn parts before use.
- Ensure the hitch ball is fully seated in the coupler ball pocket and the latch is closed.
- Use safety chains and ensure trailer lighting complies with regulations.
Installation Instructions:
Pre-Installation:
- Verify no interference from the tow vehicle, tongue, ground, or mounted accessories during operation.
- Ensure set bolts face the towing vehicle.
- Attach gussets as low as possible to support the outer tube.
- Avoid heat damage to the coupler during welding.
Welding:
- All welding must be performed by an AWS-certified welder.
- The outer tube must be rigidly attached to the trailer to support the rated load.
Post-Installation:
- Ensure the coupler remains vertical for proper operation.
- Confirm that the coupler operation has not been impaired.
- Apply included labels and remove pre-mask tape after painting.
Operating Instructions:
To Couple:
- Block trailer wheels.
- Align the hitch ball beneath the coupler.
- Set the locking pin in the open position.
- Lower the trailer onto the hitch ball and ensure it is fully seated.
- Slide the locking plate into the closed position.
- Set the locking pin to secure the coupler.
To Uncouple:
- Block trailer wheels.
- Set the locking pin in the open position.
- Raise the trailer from the hitch ball.
Maintenance:
- Perform the following annually:
- Check hardware torque (125 ft-lbs).
- Grease the ball pocket.
- Oil pivot points with SAE 30 wt. motor oil.
- Inspect retaining pin and replace if necessary.
Warranty Information:
- Three-Year Limited Warranty:
- Covers defects in materials and workmanship under normal use and service.
- Exclusions:
- Normal wear and tear.
- Damage due to misuse, overloading, or improper installation.
- For warranty claims, retain your purchase receipt and contact the manufacturer or authorized retailer.
Additional Notes:
- Gussets must extend to within 3” of the bottom of the outer tube for rated load support.
- For high-load or rough-service applications, additional reinforcement and banding may be required.
- Replacement parts are available through authorized retailers.
For technical support and assistance, visit www.trailerjacks.com or call 877-869-6690.
Attention: This is a summary of the installation procedure. For complete installation instructions, including diagrams and detailed information, please download the full installation PDF.