How do I determine the correct height requirement for my boat trailer tongue jack?

When selecting a tongue jack for your boat trailer, you need to match the jack’s travel height and maximum tongue height to your trailer’s coupler height and towing needs.

Step 1: Park on level ground
Ensure your trailer is on flat, stable ground before measuring.

Step 2: Measure coupler height
Measure from the ground up to the bottom of the trailer coupler. This is your minimum required height.

Step 3: Add clearance for hitching
Add at least 4 inches to your measurement. This ensures the tongue jack can lift the coupler high enough to clear the ball on your tow vehicle. This required number should fall within the jack’s maximum tongue height.

Step 4: Check the jack’s travel height
A tongue jack has a specified travel height, which is the total distance it can extend or retract. Make sure the jack’s travel range covers:

• Your minimum height (so the jack retracts short enough to sit safely above ground when towing).
• Your maximum tongue height (so the jack extends high enough to lift the coupler clear of the hitch ball).

Boat trailer–specific considerations

• Saltwater vs. freshwater: Use galvanized or zinc-coated jacks for corrosion protection in saltwater environments.
• Capacity: Pick a jack rated for 10–15% of your trailer’s GVWR (gross vehicle weight rating), which matches typical tongue weights.
• Jack style:
  • Wheel jacks make it easier to maneuver the trailer by hand on pavement.
  • Footplate jacks give better stability on dirt, gravel, or ramps.
• Clearance when stored: Ensure the retracted or swivel position clears the trailer frame and doesn’t interfere with loading or launching.