Truck Alignment Guide

Key Points

- Heavy-duty truck alignment is essential for maintaining the suspension system of big rigs and heavy-duty trucks, affecting both operation and safety. It involves adjusting the truck's suspension system to ensure tires meet the road at the correct angle, focusing on axles and tires rather than the wheels themselves.

- The alignment process is performed by trained diesel technicians using electronic sensors to measure angles on each wheel, comparing them to vehicle specifications. Adjustments may include caster, toe and thrust angles, along with an overview of the suspension system to identify any worn or broken parts.

- Proper alignment is crucial for preventing irregular tire wear, maximizing tire lifespan, improving road performance and ensuring fuel efficiency. It also reduces driver fatigue by keeping the truck moving straight without extra steering effort.

- Signs that a vehicle needs alignment include steering wheel drifting, abnormal tire wear, steering wheel vibrations, noisy steering or squealing tires. Regular checks and alignments are recommended at least once a year to avoid these issues.

- Professional semi truck alignment offers accurate results, extending tire life, enhancing fuel efficiency and improving vehicle safety, which helps prevent costly future repairs. While minor adjustments can be made by individuals, professional alignment by a diesel technician is advised for precise alignment.

Heavy-duty truck alignment is critical for truck suspension systems, especially for big rigs and heavy-duty trucks.

For that reason, understanding the process is critical – both for operation and safety.

But what exactly does getting an alignment do? What does it look like? How can maintaining this practice affect these technologies long term?

Keep reading to learn more about heavy-duty truck alignment and how it works.

What Is Alignment?

Over time, the suspension system can start to experience wear and tear. This can happen more quickly if a vehicle is being used consistently, which is often true in the case of semi trucks and heavy-duty vehicles.

Alignment is a term used to describe the adjustment of the truck’s suspension system. The suspension is connected to a vehicle’s wheels and helps allow them to travel and pivot as needed. An alignment is performed to make sure that the tires are meeting the road at the right angle.

Truck wheel alignment is not an adjustment of the wheels themselves, but of the axles and tires to ensure that the wheels are pointing straight and in the right direction.

Are Truck Alignments Required?

Truck alignments are important for maintaining the vehicle's performance and safety. Proper alignment ensures that the truck's wheels are set to the optimal position as per the manufacturer's specifications. Regular alignments are recommended as part of routine maintenance to keep the truck running smoothly and safely.

They help with enhancing tire life, ensuring your safety on the road and reducing wear and tear on the vehicle. Getting regular truck alignments can help keep components functioning properly and prevent you from needing to replace parts prematurely.

How does a diesel truck alignment work?

It takes trained diesel technicians to perform heavy-duty and semi truck alignments. To begin the process, they will get the tolerances and specifications for the specific set of wheels they’re working on. They do this by looking through a database of heavy-duty vehicles.

Angles are measured on each wheel using electronic sensors. These angles are then compared to the specifications that are listed for the vehicle using an alignment machine. Then, technicians will work to adjust different suspension angles. Some of these angles include:

• Caster: Caster refers to the angle of the steering axis when viewed from the side of a vehicle. A positive caster can occur when the steering axis tilts more toward the driver, and a negative caster refers to when the steering axis tilts toward the front of a vehicle.
• Toe: The toe suspension angle is how much tires are turning inward or outward when viewed from above. Toe-in alignment is when both tires are angled in, and toe-out is the opposite.
• Thrust: The thrust angle is used to help see if a rear axle is lined up with the front axle and the center of a vehicle. The angle is an imaginary line that comes down from the centerline of the rear axle all the way through the vehicle.

Technicians will check these suspension angles, along with kingpin inclination, axle offset and turning radius. They’ll also do an overview of the suspension system to ensure there are no broken or overly worn parts.

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Why Heavy-Duty Truck Alignment Is Important

There are many reasons why heavy-duty truck alignment for big rigs and other vehicles is important. One of them is to prevent irregular tire wear. Misalignment of tires can cause inner and outer tire wear, as well as the tread wearing down too quickly.

Commercial truck tires are also expensive to replace (the average cost is around $500 per tire), so maximizing the amount of time they can be used is important, especially for the financial sake of the fleet/vehicle owners. Proper commercial truck alignment can help ensure that tires are not being replaced earlier than needed.

Tires that are properly aligned can also improve performance on the road and ensure that rigs are traveling with the highest possible fuel efficiency.

Proper diesel truck alignment also prevents drivers from working harder than they need to, since it would keep the truck moving in the right direction. If truck drivers end up working harder than they need to, they can get fatigued and drive inattentively and/or recklessly. So, it’s crucial that tires are properly aligned to prevent this from happening.

Read: Preventive Maintenance Checklist for Diesel Trucks

Signs a Vehicle Needs Alignment

There are several signs that a vehicle needs alignment. The most common ones include:

• Steering wheel drifting: If the steering wheel is pulling to the right or left while a vehicle is traveling down the road, this can be a sign of misalignment. Keeping the wheel straight shouldn’t require a lot of effort.
• Abnormal tire wear: As mentioned before, a misaligned vehicle can cause abnormal wear and tear on tires. The tread might start to prematurely come off in unusual wear patterns.
• Steering wheel vibrations: Vibrations in the steering wheel can be caused by tires that are out of balance or misaligned.

Other signs include noisy steering or squealing tires. If you experience any of these issues, taking your vehicle to a trained auto or diesel technician is important so you can have the problems fixed as soon as possible.

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How often should a truck alignment be done?

Truck alignments should generally be checked every 10,000 to 12,000 miles, or at least once a

year. However, the frequency can vary based on several factors, including:

1. Driving conditions: If the truck is frequently driven on rough or uneven roads, more frequent alignments may be necessary.
2. Load weight: Trucks that regularly carry heavy loads might require more frequent alignments due to the added stress on the suspension.
3. Signs of misalignment: If you notice uneven tire wear, the truck pulling to one side, or a vibrating steering wheel, it's a good idea to have the alignment checked regardless of the mileage.
4. Manufacturer's recommendations: Always consider the manufacturer's guidelines for alignment intervals.

FAQs

1. What is semi- truck alignment and why is it important?

Semi truck alignment refers to the adjustment of a semi truck's wheels and axles to correctly align them to the truck's centerline. This is crucial for maintaining optimal tire wear, fuel efficiency and ensuring the truck handles correctly on the road.

2. How often should I get my commercial truck’s wheels aligned?

The frequency of wheel alignment depends on various factors, including the truck's usage and condition. However, a general rule of thumb is to get them checked every 10,000 to 12,000 miles or at least once a year.

3. What are the signs that my truck’s wheels are out of alignment?

Signs your truck wheels may be misaligned include uneven or rapid tire wear, steering wheel vibration, a steering wheel that's off-center when driving straight and a vehicle that pulls to one side.

4. Can misaligned wheels affect the performance and safety of my heavy-duty truck?

Yes, misaligned wheels can negatively affect your truck's performance by causing decreased fuel efficiency and irregular tire wear. They can also cause safety issues by compromising steering control.

5. What are the benefits of getting a professional semi truck alignment?

A professional semi truck wheel alignment ensures accurate results, extends tire life, improves fuel efficiency and enhances overall vehicle safety. All of this helps to prevent costly future repairs.

6. Are there specific alignment specifications for heavy-duty trucks?

Yes, heavy-duty trucks have specific alignment requirements that differ from regular vehicles due to their larger size and the increased load they carry. These specific requirements are typically provided by the truck manufacturer.

7. How long does diesel truck wheel alignment take?

The time it takes to align the wheels of a diesel truck varies depending on the vehicle's condition. Typically, wheel alignment for trucks can take between 2 to 4 hours.

8. Can I do my own commercial truck wheel alignment, or should I hire a professional?

While minor adjustments can be made yourself, it's best to hire a professional diesel technician for commercial truck wheel alignment. They have the necessary experience and specialized tools to ensure precise alignment.

Of course, you can develop these industry skills yourself in a diesel technician training program, like the one offered at Universal Technical Institute (UTI)! This 45-week program can help you learn how to diagnose, maintain and repair different systems on diesel engines and vehicles, including the skills it takes to perform a truck alignment.^1,7

9. What are the potential consequences of neglecting to align the wheels of my semi truck?

Neglecting wheel alignment for trucks can lead to premature tire wear, decreased fuel efficiency, potential damage to other components and compromised vehicle safety.

10. How much does it typically cost to get a wheel alignment for a heavy-duty truck?

The cost of wheel alignment for a heavy-duty truck can vary widely depending on location and the specific service provider. On average, you can expect to pay between $200 to $600.

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Learn Heavy-Duty Truck Alignment Skills at UTI

Enrolling in Universal Technical Institute’s Diesel Technology program can help you gain the education and hands-on training required to meet the industry’s demand for skilled trade professionals.¹ 

Students can graduate in less than a year ready to pursue entry-level work with their hands on big rigs or other diesel vehicles in the industry.⁷ You can take the first step toward a future you’re excited about when you enroll today. Get more information online or call an Admissions Representative at 1-800-834-7308!