Certain places regulate strict speed limits to ensure safety on the road. Thus, trucks should have a reliable speed limiter to prevent them from exceeding speed limits on specific routes.
Aside from traffic compliance, there are also several pros and cons you should know if you want to bypass the speed limiter of your truck.
Different truck brands may have unique ways to bypass the speed limiter. This post will teach you how to do it with a Freightliner truck.
A Short Answer on How Do You Bypass the Speed Limiter on a Freightliner:
There are three ways to bypass the speed limiter of a Freightliner truck. The first is installing a chip or control unit to program the truck code. The second is disconnecting the wire without replacing or installing a chip or an ECU. Lastly, it is by using the ECU programmer.
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What are the Typical Speed Limitations on Freightliner Trucks?
Most Freightliner trucks depending on the year and model are governed at a speed limitation of 65 – 70 miles per hour.
These speed limits are usually programmed into the truck’s computer box to give a desirable fuel-to-mileage ratio considering typical speed regulations in the state.
Freightliner trucks can reach speed limits well over 70 mph when ungoverned however the fuel economy isn’t that great at these speeds.
What is a Speed Limiter on a Freightliner Truck?
A speed limiter on a Freighliner truck essentially limits the truck’s maximum speed to a specific speed limit set by the truck manufacturer and may vary with various truck models and year of manufacture.
A speed limiter system consists of speed sensors and a program logged into the truck’s computer box that controls the engine’s output.
Speed limiters set on a truck typically cannot be changed without interfering with the electronic control unit program.
The speed limiter in Freightliner truck is not to be confused with an Intelligent Speed Assistance (ISA) system that serves as a safety measure to control your driving speed according to the designated speed limit in compliance with legal requirements and standard safety precautions.
With an ISA system, you can adjust the speed limiter to the allowed maximum speed as you drive. In that way, you can prevent breaking traffic regulations.
Where is the Freightliner Speed Limiter or Governor Located?
The speed limiter or governor is a device you can install in the ignition control module (ICM) connected to the electronic control unit (ECU).
How does a Speed Limiter or Speed Governor Work?
The speed limiter in Freightliner trucks works as a sensor to detect the current speed as you drive and send it to the engine’s computer.
Once you reach the speed limit, the computer system will start preventing the airflow and fuel from going to the engine, so you can no longer increase the speed as you drive.
However, you can override the predetermined speed limit when needed. If you want to speed up, you can try to push the accelerator down hard to make it work without affecting the braking system.
How to Disable the Speed Governor on Freightliner?
If you need to disable the speed governor of your Freightliner truck, you need an ECU programmer.
It is a speed limiter device that allows you to write the new code on the computer to the truck’s ECU.
The ECU programmer will replace the current ECU of your truck and give you a chance to recreate the code to disable the governed speed.
However, before getting an ECU programmer, ensure it is compatible with your truck because not all available ECU programmers can work with all truck models.
How Can the Freightliner Speed Governor be Adjusted?
Adjusting the speed governor of your Freightliner is so fast and easy.
First, locate the screw below the regulator’s arm and loosen it. Then, push it to open the throttle.
Turn counterclockwise the clamp connected to the controller shaft. It will now allow you to adjust the controller shaft.
Can you Remove the Speed Limiter on a Freightliner Truck?
Speed limiters exist for safety reasons. However, you may want to remove it on certain occasions, such as when you are in a rush for an emergency.
Once you remove the speed limit of your Freightliner truck, you can drive faster than your usual speed and avoid difficulties with the engine and transmission.
Driving at a higher speed will allow you to have lesser transmission and engine noise. You will also notice lower fuel consumption. Thus, you can go for longer distances without compromising your truck’s engine power.
Removing a truck’s speed limiter will change its ECU, causing the OEM parameters to prevent slowing your vehicle.
Is it Legal to Bypass or Override the Speed Limiter on a Freightliner Truck?
The legality of removing the speed limiter of your truck depends on which country you live in.
The countries in the European Union, Australia, Japan, and Canada (particularly in Ontario and Quebec), require speed limiters or governors in heavy-duty trucks.
In the U.S.A., there is currently no rule prohibiting the removal of speed limiters however this may change soon as the FMCSA is advocating for regulations to have speed limiters set on commercial vehicles.
Thus, if you are outside the United States, you must check with your country’s regulations regarding speed governors and comply with them to avoid possible violations.
How to Bypass the Speed Limiter on a Freightliner?
To bypass the speed limit of your truck, you need to have a chip or a control unit specifically made for your truck model.
You need to connect this chip to the factory settings of the truck, so you can change its programming code and allow you to bypass the speed limit.
Once you install the chip or control unit to the computer system of your truck, you will no longer see speed restrictions when driving.
Another way to bypass the speed limiter is by disconnecting the wire without installing a new chip or an ECU.
Before you remove the wires, ensure the one you will remove is the wire connecting to the ECU and ignition circuit. By eliminating the cables attached to them, you successfully bypass the speed limiter of your truck.
If you want to keep other features, such as the immobilizer, to continue working, you can replace the ignition switch and bring it to a specialist for configuration.
Pros and Cons of Bypassing the Speed Limiter on a Freightliner
Just like any other feature in a vehicle, there are pros and cons you should weigh to help you take advantage of this particular feature.
When it comes to bypassing the speed limiter on a Freightliner, here are the pros you will encounter:
- You can drive faster when you need to overtake other trucks in certain instances.
- You can have lesser engine and transmission noise when driving above the set limit speed.
- You can drive longer distances without limiting your truck’s engine power.
- You can drive faster and arrive at your destination to save more time and productivity.
Here are the cons of removing the speed limiter on your Freightliner truck:
- Using an ECU programmer to remove your Freightliner truck’s speed limiter or governor may require you to replace the chip or control unit to restore the damages from doing this action.
- You will find it complicated to restore the factory settings of your truck’s computer system once you install a new chip or control unit.
- If you disconnect the wires of the ECU to the ICM, you risk the deactivation/malfunctioning of other safety features.
- If you live in a country or area that restricts the removal of the speed limiters, you may be caught in a traffic violation since it can cause harmful incidents on the road.
As you can see, there are two sides to the coin that you need to consider when you decide to bypass the speed limiter of your Freightliner truck.
Where to Take Your Freightliner for Speed Limiter Bypass?
Truck owners and operators have the authority to decide whether they want to remove the speed limiter on their Freightliner truck.
They only need the correct chip or control unit to program or code it to their truck’s computer system.
If you are not the owner of the truck and only working as a driver, you can seek assistance from the truck owner or the company where you work.
Specific locations do not allow the removal of speed limiters on trucks. Thus, you should seek assistance from the owner or company on how you can deal with controlling the speed of your Freightliner truck.
While bypassing the truck speed limiter is possible, you should seek the expertise of a professional with experience in software upgrades to a truck’s ECU system and one that can offer warranties for workmanship.
This will avoid you having to deal with any headaches in the future and prevent any other truck malfunctioning associated with software reprogramming.
