Round Tube Gooseneck Stem Selection
Learn if you have a 4" round or 100mm (3-15/16") stem and whether it has straight or angled pin holes. There are round and square inner tube stems.
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If you have a round stem gooseneck, this guide will help you know which gooseneck hitch and coupler to order. Tube size can vary from 100mm (3-15/16") to 4" in diameter. Measuring through the pin holes can usually tell you the size. If it is slightly less than 4", it's a 100mm (3-15/16") stem. Square stems can be 100mm (3-15/16"), 4" or 4.5". This guide is for round tube stem goosenecks.
If the pin is angled on a metric 100mm (3-15/16") stem then the pin angle is greater than if it is angled on a 4" stem. Straight pin holes are the least common. A 4" round stem with angled pins is the most common. If it has a Bulldog sticker, it is going to be a 4" stem with angled pin.
What to check
- Tube size can vary from 100mm (3-15/16") to 4" in diameter. Measuring through the pin holes can usually tell you the size — if it's slightly less than 4", it's a 100mm (3-15/16") stem.
- If the pin is angled on a metric 100mm (3-15/16") stem, the angle is greater than it would be on a 4" stem.
- If you are not sure, call 587-897-4625 or message us a picture of your stem.
Which is stronger, a 5th wheel or a gooseneck?
Gooseneck hitches can pull more — up to 40,000 pounds, at least 13,000 pounds more than the best fifth wheel hitch. This applies to gooseneck hitches with a square stem and a 3" ball coupler. There are also gooseneck hitches rated at 30,000 lbs GTW with 2-5/16" ball couplers. Shocker Hitch manufactures both.
Gooseneck stem selection video
Pick your stem size and pin style in the configurator and it filters to couplers that fit.
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