Whether you’re navigating a crowded campground, backing into a tight storage spot, or making sharp turns in city traffic, there’s always the risk of your trailer getting a little too close for comfort. This is especially true for people using short-bed trucks or towing trailers with wide front caps.

One simple yet highly effective solution to this problem is a king pin extender. But what exactly is a king pin extender, and how does it work with a fifth-wheel hitch?

What Is a King Pin Extender?

A king pin extender is a heavy-duty towing accessory designed to increase the distance between the trailer and the truck’s cab or bed. It mounts directly to the trailer’s existing king pin and provides a new connection point several inches forward, effectively extending the length of the king pin.

This extra distance can solve a variety of common towing problems. For instance:

• Preventing the trailer’s front corners from hitting the truck cab during sharp turns.
• Creating space for truck bed accessories such as toolboxes or auxiliary fuel tanks.
• Improving turning clearance for short-bed trucks.
• Helping to level the trailer when hooked up to a specific truck and hitch combination.

Think of a king pin extender as a spacer that moves the pivot point backward just enough to give you room to maneuver safely and efficiently.

How a Fifth Wheel Hitch Works

To fully understand the role of a king pin extender, it helps to know how a standard fifth-wheel setup functions.

A fifth wheel hitch is mounted in the bed of your truck, typically above or slightly ahead of the rear axle. The king pin on the front of the trailer slides into the jaws of the hitch and locks securely in place. This connection provides a very stable towing setup, which is why fifth wheels are so popular among RVers and heavy-duty haulers.

However, this stability comes at a cost — limited turning clearance. On a long-bed truck, there’s generally enough space between the cab and the trailer for smooth, safe turns. On a short-bed truck, or with a wide-bodied trailer, the nose of the trailer can easily collide with the cab or any gear stored behind it. This is where a king pin extender comes into play.

How a King Pin Extender Integrates with a Fifth Wheel

When you add a king pin extender to your towing setup, it sits between the trailer’s king pin and the truck’s fifth-wheel hitch. Here’s how the connection sequence looks:

Trailer → Original King Pin → King Pin Extender → Fifth Wheel Hitch

The extender slides over the original king pin, locks into place, and provides a new king pin location that sits several inches forward. Most extenders offer an additional 8–12 inches of clearance, which can make a dramatic difference when it comes to preventing truck-to-trailer contact.

From the truck’s perspective, nothing changes — you still connect to a king pin in the usual way. The difference is that now you have extra space to work with, which can improve safety and make your towing experience much smoother.

Benefits of Using a King Pin Extender

Adding a king pin extender to your fifth-wheel setup offers several clear advantages:

1. Increased Cab Clearance

The most obvious benefit is extra room between the trailer and the truck cab.
This prevents expensive and frustrating damage caused by the trailer nose hitting the cab during sharp turns. It’s especially important for short-bed trucks, which simply don’t have as much natural clearance as long-bed models.

2. Space for Bed Accessories

Many truck owners like to use toolboxes, fuel tanks, or cross-bed storage solutions. Without an extender, these items can interfere with the trailer’s overhang. By shifting the connection point backward, the extender provides extra space for these useful accessories.

3. Easier Maneuverability

Backing up a fifth-wheel trailer into a tight camping spot or driveway can be nerve-wracking. With additional clearance, you’ll have more room to make corrections without worrying about a collision.

4. Trailer Leveling Assistance

Some extenders slightly raise or lower the connection point, which can help level the trailer. A level trailer not only tows better but also reduces wear on tires and suspension components.

Choosing the Right King Pin Extender

When selecting a king pin extender, you’ll need to consider several important factors:

Weight Capacity

The extender must be rated to handle the Gross Trailer Weight (GTW) and Pin Weight of your fifth wheel.
For example:

• If your trailer has a pin weight of 2,000 lbs., the extender should be rated well above that number to ensure safety.

Manufacturer Compatibility

Some trailer and hitch manufacturers do not approve the use of extenders. This is because the extender changes the geometry of the hitch point, potentially adding leverage that could stress the trailer frame.
Always check your trailer’s manual and speak with the manufacturer before installing an extender.

Length Added

Most extenders add 8–12 inches of clearance, but exact measurements vary. Be sure to measure carefully so you don’t exceed legal length limits for your vehicle and trailer combination.

Build Quality

Since king pin extenders bear a significant amount of force, they must be constructed from high-strength steel and feature durable, well-engineered locking mechanisms. Avoid cheaper, low-quality options that may fail under stress.

Safety Considerations

While a king pin extender is a valuable tool, it’s important to follow proper safety guidelines:

• Regular Inspections:
  Check the extender for signs of wear, cracks, or loosened bolts before every trip.
• Proper Installation:
  Ensure the extender is installed correctly and securely before connecting the trailer.
• Follow Weight Ratings:
  Never exceed the rated capacity of either the extender or your hitch system.
• Legal Compliance:
  Different states and provinces have maximum length limits for truck-and-trailer combinations.
  Be sure your rig remains compliant.

Real-World Example

Imagine you own a short-bed pickup with a toolbox mounted right behind the cab.
You recently purchased a wide-body fifth-wheel trailer for family camping trips. During your first few practice turns, you realize the front of the trailer comes dangerously close to both the cab and the toolbox.

Without a king pin extender, you might have to remove the toolbox or limit your turning radius — both of which are inconvenient. By adding a king pin extender, you gain an extra 10–12 inches of clearance, protecting your truck and gear while allowing for sharper, safer turns.

This small, relatively inexpensive piece of equipment transforms your towing experience and adds peace of mind.

Conclusion

A king pin extender may seem like a simple piece of hardware, but it plays a vital role in many fifth-wheel towing setups. By moving the pivot point backward, it provides extra clearance, improves safety, and opens up space for accessories and gear in the truck bed.

For short-bed truck owners, or anyone towing a wide-bodied trailer, a king pin extender can make the difference between a stressful towing experience and a smooth, worry-free journey.

Before purchasing one, always check your trailer and hitch manufacturer’s guidelines, verify weight ratings, and ensure compliance with local laws. When chosen and installed correctly, a king pin extender is a reliable, durable solution that helps you get the most out of your fifth-wheel setup.