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How To Inflate Semi Truck Tires? (9 Facts For Beginners!)

Getting your tires busted while on the road is a bummer, especially when you are in a rush. 

Calling a technician to fix it as soon as possible can also be a hassle, especially when everybody is unavailable.

For drivers, it is optional to understand how to change or inflate tires because it is usually a mechanic’s job. 

However, it is a plus to learn how this is done. 

And for novice mechanics, this is the perfect time to learn how to inflate tires properly.

In just a few minutes, you will be able to learn how to inflate semi-truck tires!

A Quick Answer on How to Inflate Semi Truck Tires:

To inflate semi truck tires, first, prepare the air pump. Second, look for the tire’s valve and connect the hose to the valve. Lastly, fill it with compressed air or nitrogen. Ensure that the semi-truck tires are inflated to the correct pressure according to the manufacturer’s recommendation.

What Fluid Can You Fill Semi Truck Tires With?

Packing up car and truck tires with liquid mixtures in the past years became a big business. Some even considered it to be an investment. 

This is also the path for semi trucks. Water is the cheapest way to inflate your tires with liquid. 

However, doing it without proper care can cause more harm than safety. Hence it is not recommended.

In recent years, nitrogen has become the most common and commercialized way to incorporate fluid into your truck tires. 

Before its boom, NASCAR and NASA had already been using nitrogen to inflate because its properties make the tire pressure last longer.

Some agricultural trucks use a mixture of calcium chloride and water. This is a choice for most farmers because they are safer if tractor tires burst. 

The use of other chemicals might affect the soil and agricultural production. 

Which Fluid is the Best for Semi Truck Tires and Why?

Currently, nitrogen is the best fluid to fill your tires with. Some people even compare nitrogen with compressed air. 

While nitrogen is one of the main components of air, a study by Bridgestone, a tire manufacturer, suggests that inflating the tires with compressed air loses 2 PSI per month. 

In comparison, the ones inflated with nitrogen lose 2 PSI within six months.

The cause of this is the other components of air. Oxygen and vapor are still present in compressed air. 

The molecules of both these components are smaller than that of nitrogen, which causes them to pass through the tires’ walls easier.

Another advantage of using nitrogen in tires is that it helps maintain the rims and steel cords of the tires. 

Steel is known to be reactive when it has contact with oxygen, causing rust on metal. 

On the other hand, nitrogen does not cause any of these problems.

The vapor component of compressed air also affects the pressure on tires. Vapor is good at conducting heat which causes the tires to run hot. This can be avoided when nitrogen is used to inflate tires.

What Tools are Needed for Inflating Semi Truck Tires?

You need five main things to inflate a semi truck’s tires successfully: a tire chuck, a gauge, a hose, a regulator, and the fluid or air compressor. 

Each of these tools is connected to the other to ensure that the tires are properly filled without it bursting.

  • Tire chuck: these are the small things in the tip of the equipment which ensure that all the compressed air is transported inside the tire. They are the tire valve stems.
  • Tire gauge: tire gauge is a device that measures the tire’s pressure. It ensures or serves as a guide to determine if more pressure is needed or to stop.
  • Hose: a hose for inflating tires is also necessary for getting the job done with less hassle. You do not want to move your equipment for each of the tires of the truck.
  • Regulator: from the word itself, a regulator is a device that regulates the amount of air or fluid entering the tire. 
  • Compressor: an air compressor is a device that produces the air that goes into the tire. There are numerous variants of air compressors, including portable ones.

What is the Correct Tire Pressure for a Semi Truck?

For years, the 100 PSI pressure on tires has been used as a standard for semi trucks. 

We hate to burst your bubble, but these magic numbers might not be the correct tire pressure for your truck.

There are a lot of factors to consider when inflating your truck tires. 

Some of these are the tire size, the tire type, the weight of the truck’s load, the tire brand, and temperature and weather conditions. 

All of this affects the amount of pressure that the tire needs.

How to Check Semi Truck Tire Pressure Rating?

The pressure rating of a semi-truck tire can be checked through a tire pressure gauge. 

May this also be a gentle reminder that checking your tire pressure regularly is crucial to avoid accidents on the road.

How Do you Fill a Semi Truck Tire with Air?

Filliping your semi truck’s tires with air has the same steps. 

First, find the air valve on the tire(s) that needs to be filled with air. Second, get the air hose connected to the air compressor. 

Make sure that the tire chuck is connected to the air hose. Put your air hose on the air valve, then pull it to add compressed air. 

Can You Overfill or Underfill Air Into Semi Truck Tires?

You can overfill or underfill air into your semi truck tires, but we’ll tell you, it is unsafe. 

Yes, the truck will work, it can do the regular job, but there are risks included. 

While overfilling can make your truck feel lighter, you want to avoid causing road accidents. 

On the other hand, underfilling tires might affect the efficiency of your trucks.

Dangers of Overfilling and Underfilling Semi Truck Tires

Your tire pressure affects the performance of your trucks. 

You might not feel it directly, but it can be self-evident in the long run. Overfilling your tires can cause less traction. 

Even if your driving is lighter, stopping your truck might be more challenging because of the less friction. 

Second, it is harsh and noisy. And lastly, the tires are prone to center damage.

Underfilling your tires could be better. Its effect includes less response from the truck. 

Since it is underfilled, it might be hard for the truck to move. Second, it also leads to poor and inefficient performance. 

And lastly, there is also a danger to the driver’s safety. You can test if your truck tires are underfilled when the sides of the tires are more worn than the center.

So, the next time you’re filling your truck tires with either air or fluid, take note of these things for a more efficient performance plus safety.

Do You Need a Qualified Person to Inflate Semi Truck Tires?

Well, nothing is stopping you from inflating your truck. 

However, a certified mechanic or someone with experience in inflating semi-truck tires should do the job. 

If you decide to do it, be sure you know where the valves on the tires are, and be careful not to overfill or underfill them.

Inflating your truck tires is only a small job compared to other machine work. 

But since this also affects the truck’s performance, it should also be handled carefully.

Should Semi Truck Tires be Replaced if They Lose Air?

The answer to this question is that it depends. Tires need regular checking. 

Generally, losing air on tires does not mean you need to replace them. It just only needs to be inflated. 

However, if you can see that the tires have already worn out or have a hole, it is the right time to replace them.

Generally, it takes 3 to 6 years for truck tires to be replaced unless there is an accident or unforeseen event.