Going downhill in a semi-truck is one of the most difficult driving skills to learn. It requires a combination of knowledge and experience to know when and how to safely enter, brake, and exit a downhill area. Taking the time to understand the necessary braking, shifting, and other techniques can help ensure safe travel on any downgrade.
When Going Downhill: Make sure all brakes are in good condition before beginning your descent. This includes checking the air pressure in your air brakes as well as inspecting the wear on drum brakes and slack adjusters for full adjustability. Additionally, make sure to check for any leaks or damaged components that could cause a failure during your trip.
Applying Brakes: When going downhill in a semi-truck, you should always start by applying your service brakes. These are typically found on the left side of your steering wheel and should be applied firmly but not too forcefully.
The goal is to reduce speed without locking up your wheels or overworking your brakes. You can also tap your trailer brakes if needed but be sure not to overuse them as they can cause excessive wear.
Shifting Gears: When you are descending a hill with an automatic transmission equipped truck, it is important to place the truck into a lower gear prior to beginning the descent. This will allow you to use engine braking instead of relying solely on your service brakes which can help reduce wear on them. If you have a manual transmission truck then it is important that you downshift as needed in order to maintain control of the vehicle.
Using Auxiliary Brakes: For longer descents and steeper grades, it may be necessary to use auxiliary brakes such as an exhaust brake or Jake brake system. An exhaust brake works by restricting exhaust gases from exiting out of the engine while Jake brakes work by using valves that open and close in order to create compression within the cylinders.
Conclusion:
Learning how to safely go downhill in a semi-truck requires knowledge and experience. Understanding when and how best to apply service brakes, shift gears, use auxiliary brakes such as an exhaust brake or Jake brake system are all important skills that must be mastered when driving down steep hills with a semi-truck. Taking the time to understand these techniques can help ensure safe travel on any downgrade.
