Im building a 16.5 foot deck and 3-ft tongue dual axle trailer out of an old job shack trailer. The frame was around 24′ however I will cut it to the 16.5 foot length and use the extra steel to reinforce and build out struts for the axles.
Below is some general information to calculate dual axle positions when building a trailer.
Trailer Axle Calculator Results
For a 16.5 ft deck, use the following specifications:
- Primary Pivot Point: 119 inches (9′ 11″) from the front of the cargo deck.
- Tandem Spread: Ensure equal spacing from the center hanger for both axles (typically 33-35 inches apart).
- Weight Distribution: Aim for 10-15% of GTW (Gross Trailer Weight) on the tongue.
Why this position?
- Tongue Weight: Placing the axles slightly behind the physical center of the deck ensures that roughly 10% to 15% of the total trailer weight rests on your hitch.
- Stability: If the axles are too far forward, the trailer will “fishtail” at high speeds. If they are too far back, you will put excessive downward pressure on your tow vehicle’s rear suspension, making steering difficult.