Shocker Hitch — Air Ride Towing Hitches
Shocker 40K Gooseneck 4.5in Stem with Wallace Coupler - Square Stem with Straight Pins Holes - Black

Shocker 40K Square Gooseneck Stem & Wallace Coupler for 3" Ball - 40,000 lbs - Square 4" Straight Pin, Black

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$519.99 CAD

$809.23 save $289.24

or as low as $44/mo with flexible financing — 4, 6, or 12 months. Options at checkout.

Free shipping over $150Ships from Canada1-year warranty60-day returns
Standard

SKU: WF-SQ-STR-WF40

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The details that matter

Product overview

This heavy-duty replacement 4" inner tube square gooseneck stem and Wallace gooseneck coupler for 3" gooseneck ball. Inner 4" or 100mm (3-15/16") square tube replacement gooseneck coupler that fits into a 4-1/2" outer stem tube on a gooseneck trailer.

What’s included

  • Includes a complete replacement inner square tube gooseneck stem to replace 4-1/2" along with a Wallace Forge coupler for a 3" gooseneck ball.
Full product description

This heavy-duty replacement 4" inner tube square gooseneck stem and Wallace gooseneck coupler for 3" gooseneck ball. Inner 4" or 100mm (3-15/16") square tube replacement gooseneck coupler that fits into a 4-1/2" outer stem tube on a gooseneck trailer.

Designed for 3" gooseneck hitch balls, it features a thick-wall adjustable inner square tube stem and a rugged cast steel Wallace gooseneck coupler rated at 40,000 lbs. It's a direct replacement for worn or damaged factory gooseneck stems and couplers, restoring strength, safety, and dependable performance to your trailer.

Engineered for work-ready durability, this square stem and coupler assembly is ideal for flatbeds, dump trailers, livestock trailers, equipment haulers, race trailers, and more. The adjustable stem allows you to set proper trailer height, while the traditional Wallace coupler delivers a proven, secure connection for heavy loads.

Designed to weld to your existing outer gooseneck tube for a solid, professional installation. Installs in minutes. California Residents: Prop 65 Warning

All features & technical notes

Features

4" Square Gooseneck Stem & Wallace Gooseneck Coupler for 3" Ball: Inner 4" square tube replacement gooseneck coupler that fits into a 4-1/2" outer stem tube on a gooseneck trailer. Completely replaces your factory gooseneck stem & coupler. Installs in minutes. Featuring a textured matte black powder coat finish.

Complete Replacement Square Stem & Wallace Goose Coupler for 3" Ball: Replaces your factory inner tube square stem and coupler as a single unit for a clean, strong upgrade or repair. Heavy-Duty Thick-Wall Square Tube Stem for Superior Strength: Built to handle extreme towing loads and demanding trailer applications without flex or fatigue.

Extra Reinforced Plating at Weld Area for Long-Term Durability: Additional plating at the coupler-to-stem connection ensures a strong weld and long service life. 4 Adjustment Holes for the Height You Need: Features 4 adjustment holes spaced 2-3/4" apart, allowing precise trailer height adjustment. 1" diameter holes for 4" square stem. 40,000 lbs.

Towing Capacity / 8,000 lbs. Tongue Weight: Built for heavy-duty commercial and agricultural towing demands. Includes Inner Tube Square Stem & Wallace Forge Gooseneck Coupler: Includes a complete replacement inner square tube gooseneck stem to replace 4-1/2" along with a Wallace Forge coupler for a 3" gooseneck ball.

Designed for 3" Gooseneck Hitch Balls: Compatible with standard 3" gooseneck balls commonly used on high-capacity trailers. Optional Outer Gooseneck Square Sleeve Tube: Does not include weld on outer gooseneck square sleeve tube. They are sold separately.

Installation

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$519.99 CAD

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  • 1-Year Manufacturer Warranty
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  • 20,000+ Customers
  • Ships from Canada