Truck governors are designed to prevent trucks from exceeding certain speeds. The question is, how do truck governors work? This article has the answers.

How do truck governors operate? How do they manage to maintain the vehicle’s speed to a certain limit?

Truck governors work by shutting off pulses to the ignition or fuel injectors whenever a truck exceeds the preset speed. Once this happens, the engine’s fuel supply and air will be cut off. These pulses will then be reactivated when the truck’s speed falls to the desired levels.

In this guide, we will take a closer look at what truck governors are as well as how they work. So, if you have been wondering how these devices help to limit a vehicle’s speed, then the answers are right here.

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Table of Contents

About Truck Governors

As their name suggests, truck governors are built to govern a truck’s speed. In short, they won’t allow your truck to exceed certain speeds. Even if you press your foot down on the gas pedal, your vehicle’s speed won’t go above a particular limit set in the truck governor.

Most trucking companies have installed truck governors in their vehicles. The governors in these vehicles are designed to prevent their drivers from exceeding certain speeds, thus helping to reduce accidents.

How Truck Governors Work

As mentioned above, truck governors prevent trucks from traveling beyond certain speeds. There are different types of speed limiters on the market. And the mode of operation will vary from one governor to the next. However, electronically controlled governors are currently the most popular.

Electronic governors are usually connected to the truck’s electronic control module (ECM) or control box. You can only modify these governors using specialized computer equipment. Hence, it’s almost impossible for a driver to tamper with the governor.

So, how do these electronic governors work? Well, the governor on the control box will receive a signal from the truck’s wheel speed sensors or transmission differential. The governor will then shut off pulses to the ignition or fuel injectors when the truck exceeds the set maximum speed.

These pulses will only open when the truck’s speed is lowered to the appropriate level. In short, the governor will prevent excess fuel from reaching the truck’s engine. Hence, even if you keep pushing on the accelerator pedal, the truck won’t exceed the maximum set speed.

Most of the major trucking companies in the U.S have installed governors in their trucks. These governors are designed to ensure the drivers using the trucks will always maintain safe and legal driving speeds. The maximum speed set on the governor will vary from one truck to the other. But in most cases, the speeds are usually set at 65mph, 68mph and 70mph.

Pros of Governors in Trucks

Almost every trucking company these days has installed electronic governors on their fleet. In fact, it will be hard to find a trucking company whose fleet doesn’t have governors. Here are some of the benefits of governors in trucks.

Reduced Accidents

One of the main advantages of governors in trucks is that they can help to reduce the occurrence of fatal crashes. Speed is arguably the primary cause of the majority of fatal crashes. Hence, reducing a truck’s speed can considerably help to lower the number of fatal crashes.

According to a study carried out by the Federal Motor Carrier Safety Administration (FMCSA), trucks that have been outfitted with speed limiters or governors have a 50% lower crash rate as compared to those that don’t have.

If a truck is fitted with a speed limiter, the driver will always maintain slow and safe driving speeds. And when a driver is driving at a slower speed, they can clearly see what’s ahead of them. Furthermore, they will have adequate time to react and stop the vehicle, in case there’s an emergency in front of them.

On the other hand, if a truck doesn’t have a speed governor, they may be tempted to drive at higher speeds. Consequently, it will be hard for them to react on time whenever there’s an accident ahead of them, leading to a fatal crash.

Furthermore, trucks take a longer distance to stop, compared to passenger vehicles. On average, a truck moving at 65mph will take around 525 feet to stop compared to 316 feet for a passenger vehicle moving at the same speed.

So, if the truck happened to be traveling at higher speeds, it will take even a long distance to stop, meaning a fatal crash will be unavoidable, in an emergency. Hence, installing speed governors on trucks can reduce fatal clashes considerably. And when combined with various accident mitigation technologies on trucks, speed governors can help to lessen the severity of fatal clashes or prevent them altogether.

Lower Fuel Costs

Driving a truck at a higher speed will consume more fuel, compared to driving at slower speeds. Whenever you push your vehicle to its limits, you will force it to work harder. Consequently, it will burn more fuel. Hence, installing a speed limiter on a truck can help to reduce fuel costs.

According to a report published by the U.S Department of Energy, reducing driving speeds by around 5mph to 10mph can improve fuel efficiency by approximately 7% to 14% respectively.

And considering that trucking companies want to maintain a healthy bottom line, installing speed limiters in their trucks can help in reducing fuel consumption. Consequently, this can help to reduce the amount of money spent on fuel. As a result, their profit margins will be higher.

Lower Emissions

As mentioned above, the faster you drive, the more fuel you will burn. And the more fuel you are burning, the higher the quantity of carbon dioxide and other harmful gases the truck will emit.

Installing a speed governor on a truck will prevent it from driving at above-average speeds. At the same time, the fuel burnt by the truck will be lower, resulting in lesser emissions of harmful gases to the atmosphere.

Lesser Repair and Replacement Costs

Driving at higher speeds may lead to serious crashes. And when this happens, the truck may end up incurring serious damage, which may need thousands of dollars to fix. Also, the truck may end up being totaled, meaning it will have to be replaced.

The problem is that if the crash happened as a result of the truck driver’s fault, the insurance company will not handle the repairs or replacement. In this case, the trucking company will have to handle everything. And if such issues happen frequently, the repair or replacement costs can eat into their profit margins.

By installing truck governors, the driver will be forced to drive at slower and steadier speeds, thus reducing clashes. And if a clash was to occur due to the driver’s fault, the damage will not be extensive. Hence, installing speed governors can help to reduce the money spent on truck replacement or repairs.

Wrapping It Up

There you have it, all the information you need on how truck governors operate. So, if you have been wondering how they work, then the information we’ve shared here should answer any questions that you may be having concerning these devices.

How Do Truck Governors Operate?

About The Author

Charles Redding

Charles Redding

I've spent many years selling cars, working with auto detailers, mechanics, dealership service teams, quoting and researching car insurance, modding my own cars, and much more.

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