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Semi Trucks: 16 Popular Questions Answered (For Beginners)

In this article, we’ve answered some of the most common beginner questions around semi trucks that you may find helpful.

Here are the 16 most popular questions answered…

Is a Semi Truck considered an Automobile?

Semi trucks are not considered automobiles. They are classified as commercial vehicles. A commercial vehicle is any truck which exceeds 10,000 pounds, and is used for monetary purposes primarily. Semi trucks are heavy-duty trucks that are driven by people with a special license called a CDL. 

Under the technical definition of a vehicle, yes semi trucks are propelled by some fuel or propellant, but this can be a lot of things.

Generally, the distinction between a normal vehicle used by people just for getting from point A to point B, a commercial vehicle is used for monetary gain and exceeds a certain weight. 

Do I need a CDL to Drive a Semi Truck?

You must have a valid class A CLD license to drive a semi truck for commercial purposes, as you will usually exceed the 26,001 pounds limit when hauling loads. Normally, you will not need a class B or C to operate a truck under the 26,000 weight limit as long as you don’t make money by driving it.

A CDL license is a special class of license used for vehicle operators who drive their vehicles for monetary gain. 

Class A is the highest class of CDL, and also permits the owner to operate classes B and C.

There are some variables between states about whether you may own a semi truck without owning a CDL. Most states concur, however, that to operate a semi truck you must own a class A CDL.

However, trucks under the 26,001 pounds limit usually are exempt from the CDL requirements as long as you are driving them for recreational or personal reasons.

For example, you will likely not need a class C CDL to drive your pickup truck, unless you drive it for monetary purposes. 

Do I need a CDL to Purchase a Semi Truck?

Typically, you do not need a CDL to purchase a semi truck of any size or weight (be sure to check your local authorities, however). A CDL is required to operate a commercial vehicle, but the buyer does not need one. You will need a driver with a valid CLD to drive the semi truck purchased.

To lend some clarity on this subject, consider that if you own a trucking company, where you employ drivers and purchase the vehicles they drive.

But, you don’t actually do the deliveries or drive the trucks yourself, there is no need for you to obtain a CDL then. 

Semi trucks require a lot of skill to operate, with their size, weight, and the value of the products they typically carry, there’s a lot expected of the driver. 

There is a lot of damage which can be inflicted on a number of motorists if the driver isn’t sufficiently skilled to operate the vehicle.

This is why CDL licenses are required for operating a big rig.  

What Credit Score is needed to buy a Semi Truck?

The credit score you’ll need to purchase a semi truck depends on a number of factors, but on average you can expect to need at least a 600 score. This is only an average of course, and some sellers or lenders may require it to be higher. 

Purchasing a semi truck is a daunting endeavor. Maybe you are starting your own private shipping company, or simply running loads privately. Either way, you’ll need a truck. 

Semi trucks can cost anywhere between $100,000-$600,000 depending upon the brand, the quality, and the age of the truck. So, you know you’ll need some cash. 

To purchase a new semi truck, you can expect to have a lot of upfront costs.

Most sellers require up to 20% of the truck cost as a deposit upfront. This wouldn’t be so alarming if the trucks weren’t so costly. 

Additionally, there is a high interest rate for most truck purchases as well. Normally around 5-7% interest rates. But, we will discuss this further in the next section. 

How Much is a Down Payment for a Semi Truck?

Most financing plans require that you give a down payment of 20% of your truck’s purchase price. This means if you are purchasing one of the less flashy brands, you will probably expect to pay $40-$60,000 upfront. 

As stated above, the upfront costs for a semi truck can be a bit daunting. Although, there are financing plans available to those looking for a new or used semi truck. 

The idea is to try to find what your needs are, and how much you feel you’ll be demanding of your truck. 

How many Cylinders does a Semi Truck have?

The typical semi truck has a 6 cylinder turbo-diesel engine. The 6 cylinders are arranged in an in-line (straight six) configuration and vary from 11L to 16L in capacity with 13L to 15L most common. Six-cylinders produce more torque, are more efficient, and less complex than V8 semi truck engines.

There are also semi trucks with V8, V10, and V12 engine configurations, however, they are rare and uncommon.

Cylinders are the tools that convert your fuel into power for your truck, so the number of cylinders is usually closely linked to the amount of torque your engine creates. 

The truck most of us think of when we hear the word “semi truck” is a large tractor hauling a long trailer behind it barreling down the highway. 

These are the class 8 or sometimes 7 semi trucks, which have 18 wheels and a lot of torque for hauling huge loads long distances. 

Torque is the amount of power your truck has to haul heavier loads. The torque is important to the function of your truck, and the ease at which they travel uphill. 

At one time, semi trucks had massive fuel tanks which had up to 12 cylinders, but these engines were switched for the more fuel-efficient models. 

Is Semi Truck Diesel the same as Car Diesel?

Semi truck diesel and car diesel are both the same diesel fuel. Both Semi trucks and cars use either grade of diesel i.e. Diesel #1 and Diesel #2, depending on fuel price and seasonality. However, cars can use diesel as well as gasoline. Semi trucks that use gasoline are not very common in the U.S.

Diesel is the fuel used by truck drivers across the USA, and is different from natural gas used by most traditional vehicles. 

You may be wondering why the gas station pumps are sometimes different? This is due to the size of the semi truck’s fuel tank. 

A semi truck’s tank is much larger than the average automobile, and this means that the fuel flows much quicker for a semi truck than in an automobile. 

There are actually a number of laws regarding the speed at which gasoline and diesel can dispense from a pump to prevent damaging your car.

However, if semi trucks were forced to fill up at this rate, it would waste way too much time. 

What is the Front of a Semi Truck called?

The front of a semi truck is called a tractor or power unit. It has a windshield, fender, compartment for the engine, a cab where the driver sits, and usually a sleeper. Tractors come in different shapes and sizes and they either have a hood covering the engine (long nose), or a cab-over engine.

A tractor trailer, or semi truck, have many names which are given to them. And, these numerous names don’t stop with just the entire truck itself. 

There are many “nick-names” for different parts of the semi truck, but let’s find out more about what they’re really called. 

Even though the front portion which hauls the trailer is called the “tractor” there are many parts of the truck which are also considered the “front”. 

The dolly is the axle portion that attaches the trailer to the tractor and bears the majority of the weight of the trailer.

This portion is not usually overly visible to the naked, untrained eye, but it is part of the “front” and very important. 

A super handy cheat sheet to help you learn more about the different parts of your semi truck can be found here.

What is the back of a Semi Truck called?

The back of the semi struck is called the trailer. It’s the portion of the semi truck that carries the goods. Another important part of the back of the semi truck is the 5th wheel. The 5th wheel is not actually a wheel, it’s the axle and the hitch on which the trailer is attached and controlled.

The back portion of your semi truck is one of the most valuable parts, if you consider what you’re carrying across the country. 

These portions are called a number of nicknames, but some of the most common are “trailer” or sometimes misnomered as “hitch”.

What kind of Asset is a Semi Truck?

A semi truck is considered as a fixed asset or an operating asset since it is generally used for comercial purposes. Both the tractor and trailer of the semi truck are assets that depreciate over time, usually over a 3-5 year depreciation schedule, due to wear and tear as it is used.

A semi truck is a huge investment to anyone looking to enter the business. There is always the option to purchase a used truck (this has its own costs). 

A semi truck is typically treated as similar to a trailer purchase. For example, if you purchase a trailer home in a trailer park that is not connected to the ground, the value decreases in value. 

Similarly, a tractor and it’s trailer decrease in value for similar reasons. The use of a tractor goes down the more use it takes, and the trailer goes down due to wear and use. 

Is a Semi Truck Considered Listed Property?

Semi trucks are considered listed property largely as it can be defined as any property owned by a business for business purposes which decreases in value over time. These items can include boats, semi trucks, motorcycles, or other similar items. 

Semi truck value decreases as it experiences mileage and wear on the engine. The wear affects the operation of the truck and can affect its value. 

You need to think that drivers want to get up to 40-60,000 miles every year from the semi truck. And, if you’re selling it used, the price will be down due to these reasons. 

Are Semi Truck Convoys Illegal?

Semi truck convoys are considered illegal. It was common in the older days as it helped truckers speed to keep up with the shedules and only risk one truck being caught by the police speedtrap, but this is extremely dangerous. Semi truck conveys, however do take place with permission from DOT.

When semi trucks travel close together, and have the same destination, it is considered a convoy. Technically, a convoy consists of at least 2 trucks, but it can be more. These are illegal for semi trucks, however, and are very dangerous. 

However, there are semi truck convoys that take place yearly to celebrate the trucking industry such as the Truck Convoy event.

What are Chicken Lights on a Semi Truck?

Chicken lights are the smaller, LED lights which usually illuminate the outside of semi trucks. These lights, although named after old lanterns, are much brighter and serve a different purpose from deterring robbers. Rather, they help to protect the driver and other motorists traveling at night.

The story behind what are called “Chicken Lights ” on a semi truck is a rather interesting historical note.

The story goes that truck drivers back in the early 1900’s were robbed of their chickens often while traveling in dark areas. Truck drivers started adding lanterns to their trucks to prevent this. 

Do Semi Trucks have Momentum?

A semi truck in motion does have momentum proportional to its size and weight. The momentum of an object is found by the formula p=mv. A truck in motion traveling at 40 mph will have greater momentum than a smaller vehicle traveling at the same speed.  

Momentum is the velocity of an object multiplied by the mass of an object. This means that the larger the object the more mass it has to propel it. 

Likewise, the larger the object the more weight it has, and the more it is weighed down. 

Does a Semi Truck have more Inertia?

A semi truck will have more inertia than lighter vehicles such as cars and bikes since it has more mass. In terms of vehicle handling, a semi truck will have a slow response to steering commands. This is due to its high polar moment of inertia, where weight concentrations are heavy and far apart.

Inertia is described as the resistance to change the direction or velocity of a body, whether at rest or in motion. This means that it will take a greater force to move a semi truck when as rest or moving.

How many Trumoo Semi Trucks are in the U.S.?

Trumoo is a subsidiary of Dean company, which was the number 1 milk producer and distributor in the U.S. Dean food group has over 8,000 refrigerated delivery trucks on the road on a daily basis to deliver products to their consumers.

Dean, the owner of Trumoo was the top dog when it comes to milk distribution at one time, the company has suffered.

Although the number of trucks dedicated to specifically to Trumoo is not known, it is true that many drivers have lost good money as a result. 

Dean has filed for Chapter 11 Bankruptcy, and has lost many of its assets as a result.

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