Shocker 40K Square Gooseneck Stem & Wallace Coupler for 3" Ball - 40,000 lbs - Square 4.5" Diamond C Telescoupler, Black
$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.
SKU: WF-45SQ-BLK-WF40-DC
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The details that matter
Product overview
This heavy-duty replacement4-1/2" inner tube square gooseneck stem and Wallace gooseneck coupler for 3" gooseneck ball for Diamond C trailers with telescoupler bolted stem pattern. 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.
What’s included
- Includes a complete replacement inner square tube gooseneck stem to replace 4-1/2" Diamond C set bolt pattern stems, along with a Wallace Forge coupler for a 3" gooseneck ball. (Doesn't Include Bolts - Thread Pattern 3/4-10).
Full product description
This heavy-duty replacement4-1/2" inner tube square gooseneck stem and Wallace gooseneck coupler for 3" gooseneck ball for Diamond C trailers with telescoupler bolted stem pattern. 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
4-1/2" Square Gooseneck Stem for Diamond C Telescoupler with Bolted Stem Pattern Stem & Wallace Gooseneck Coupler for 3" Ball: Inner 4-1/2" square tube replacement with Diamond C bolted stem pattern gooseneck coupler that fits into a 5" outer stem tube on a Diamond C gooseneck trailer. (Doesn't Include Bolts - Thread Pattern 3/4-10).
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 4.5" square stem. 4-1/2" Stem has 4 Threaded Bolt Holes for Adjustment & fits 3" Gooseneck Hitch Balls: Replaces 4-1/2" square stem with Diamond C set bolt pattern.
Features 4 threaded 3/4-10 holes to bolt the stem into place and to set the height you need for your setup. Bolts not included. 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" Diamond C set bolt pattern stems, along with a Wallace Forge coupler for a 3" gooseneck ball. (Doesn't Include Bolts - Thread Pattern 3/4-10).
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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Installation Guide
Step-by-step videos for every Shocker family. What's in the box, what tools you need, and how long it takes.
Watch the installAir Pressure Setup
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