How Wide Is A Dually Truck

So, you're thinking about tackling a project involving a dually truck – maybe you're fitting new rims, planning a custom bed build, or even just trying to figure out if it'll squeeze into your garage. Knowing the exact width of these beasts is crucial. But finding that spec online can be surprisingly difficult, and often misleading. This article will give you the detailed breakdown you need to understand the width of a dually truck, covering everything from official measurements to real-world considerations. And to make things even easier, we’ve got a detailed diagram available for download that visually illustrates everything we’ll discuss.

Why This Matters: Purpose and Scope

Before we dive into the specifics, let’s talk about why understanding a dually's width is so important. This isn’t just about satisfying curiosity; it has real-world implications for:

Repairs and Modifications: When ordering aftermarket parts, especially wheels, tires, and body components, accurate width measurements are absolutely essential. Incorrect measurements can lead to rubbing, clearance issues, and even safety hazards.
Towing and Load Capacity: Understanding the overall width, including the protruding dually wheels, helps you choose the right tow mirrors and ensures safe operation within legal limits. Wider isn't always better; exceeding width restrictions can result in fines.
Storage and Parking: Let's be honest, these trucks aren't known for their compact size. Knowing the exact width is vital when planning for garage storage, navigating tight parking spaces, or considering carport additions.
Legal Compliance: Many jurisdictions have regulations regarding vehicle width. Knowing the dimensions of your dually helps you stay compliant and avoid potential penalties.

This article will primarily focus on the overall width of the truck at the rear axle, specifically across the outer faces of the dual wheels. We'll also touch on other related dimensions that might be relevant for your project.

Key Specs and Main Parts

Let’s break down the key components and specifications that contribute to the overall width of a dually truck:

Rear Axle Assembly: This is the core of the dually system. It’s a heavy-duty axle designed to handle the increased load and stress of dual wheels. The axle width itself is a crucial factor in determining the overall width.
Wheels: Dually wheels are typically steel or aluminum and designed specifically for dual fitment. They have a particular offset to provide adequate clearance between the tires and the truck’s body and each other. The wheel offset is critically important. A positive offset means the mounting surface is closer to the outside of the wheel, while a negative offset means it's closer to the inside.
Tires: Tire size and type significantly impact the overall width. Wider tires will obviously increase the total width of the truck. Tire pressure also plays a role, as under-inflated tires can bulge outward, affecting the measurement. Common dually tire sizes range from 225 to 245 millimeters in width, with aspect ratios varying depending on the application.
Fender Flares (Dually Fenders): These are wider than standard truck fenders to accommodate the dual wheels. They are an integral part of the dually design and contribute to the overall width of the truck. Aftermarket flares may exist.

A typical dually truck width, measured from the outside edge of one rear tire to the outside edge of the opposite rear tire, usually falls between 96 and 100 inches (approximately 8 to 8.3 feet). However, this is a general range, and the exact width varies depending on the specific truck model, year, wheel and tire configuration.

Decoding the Diagram: Lines, Colors, and Icons

The diagram we've put together uses specific conventions to illustrate the key measurements. Here’s a quick guide:

Solid Lines: Represent the actual physical dimensions of the truck and its components. Thicker lines often denote more prominent features like the axle or wheel rims.
Dashed Lines: Usually indicate theoretical or calculated measurements, such as the centerline of the axle or the intended tire clearance.
Color Coding: We've used different colors to differentiate between components. For instance, the axle might be shown in blue, the wheels in gray, and the tires in black. This makes it easier to visually separate the different parts.
Icons: Small icons might be used to indicate specific components or points of interest, such as the location of the wheel studs or the position of the brake calipers.
Dimensional Arrows: Arrows with numbers indicate precise measurements in inches or millimeters. Pay close attention to the placement of these arrows to understand what dimension is being shown.

The diagram will clearly show the overall width, the distance between the inner wheels, the fender flare width, and other relevant measurements.

How It Works: The Physics of Dually Width

The dually setup is designed to distribute weight more evenly across the axle, increasing payload capacity and stability, especially when towing. The dual wheels essentially act as two tires in one, providing a larger contact patch with the road. This increased contact area translates to improved traction and reduced stress on each individual tire.

The width of the dually setup is a direct consequence of this design. The wider the wheel spacing, the more evenly the load is distributed. However, there are practical limits to how wide the dually wheels can be. Exceeding these limits can lead to:

Rubbing: The tires can rub against the fender flares or the inner body of the truck, causing damage and noise.
Instability: Excessive width can negatively impact handling and stability, especially in crosswinds or during sharp turns.
Legal Issues: As mentioned earlier, exceeding legal width restrictions can result in fines or even impoundment of the vehicle.

Real-World Use: Basic Troubleshooting Tips

Here are some common scenarios where understanding dually width is crucial, along with some basic troubleshooting tips:

Tire Rubbing: If you're experiencing tire rubbing, first check the tire size and wheel offset. Ensure that you're using the correct size tires for your truck model. If you've recently installed aftermarket wheels, verify that the offset is compatible. You might need to adjust the fender flares or install wheel spacers (use with extreme caution and ensure they are hub-centric and high quality) to provide adequate clearance.
Wheel Alignment Issues: Incorrect wheel alignment can exacerbate tire rubbing problems. Have your truck’s alignment checked by a qualified technician. A properly aligned suspension ensures that the tires are running straight and true, minimizing the risk of rubbing.
Load Capacity Concerns: If you're consistently hauling heavy loads, ensure that your tires are properly inflated to the recommended pressure. Overloading the truck can lead to tire failure and damage to the axle. Check your truck's door jamb sticker for the maximum gross vehicle weight rating (GVWR).

Safety: Risky Components

The dually setup involves several components that can be potentially hazardous if not handled correctly:

Wheels and Tires: Improperly installed or maintained wheels and tires can lead to catastrophic failure. Always use a torque wrench to tighten the lug nuts to the manufacturer's specifications. Regularly inspect the tires for signs of wear and tear, such as cracks, bulges, or uneven wear patterns.
Axle Components: The rear axle is a critical component that supports the weight of the truck and the load. Damaged or worn axle components can lead to loss of control. Have the axle inspected regularly for signs of wear, such as leaks, cracks, or excessive play.
Wheel Spacers: While sometimes necessary for clearance, wheel spacers can introduce stress on the wheel studs and bearings. Only use high-quality, hub-centric spacers from reputable manufacturers. Ensure that the spacers are properly installed and torqued to the correct specifications. Avoid stacking multiple spacers.
Lifting the Truck: Always use proper jacking points and jack stands when lifting a dually truck. Never work under a truck that is only supported by a jack. Dually trucks are heavier than standard trucks, so you need heavy-duty jacks and stands.

Remember that working on any vehicle, especially a heavy-duty truck, requires caution and a thorough understanding of the components involved. If you're not comfortable performing a particular task, it's best to seek the assistance of a qualified mechanic.

We've covered a lot of ground here, and hopefully, you now have a much better understanding of the width of a dually truck and the factors that influence it. To further assist you in your projects, we have prepared a detailed diagram of a dually truck showing all the critical measurements. You can download it from [Link to Diagram Here]. This diagram will serve as a valuable resource when planning modifications, repairs, or any other project involving your dually truck.