Mon – Fri: 8:30am to 5:00pm (Central Time) (204) 777-1678 Canada


Understanding and Caring for Brakes in a Semi Truck

Mar 3, 2022 | Truck Driving Advise | 0 comments

Brakes are an integral part of any vehicle, but keeping your brakes in good working condition is extremely important in a vehicle weighing up to 80,000 lbs when fully loaded. For reference, your average car weighs roughly 4,000 lbs. Maintaining and replacing your brakes when needed will not only save you money in the long run, it will ensure a smoother journey and help you return home from your trip safely.

How do Semi Truck Brakes Work?

While most vehicles you see on the road use hydraulic brakes, semi trucks are simply too big for that to be a safe option. Instead, most large vehicles like heavy trucks and busses will use air brakes. But how do air brakes work?

Air brakes use a pressurized storage tank that releases air into the brake lines, creating a difference in pressure that slows the truck to a halt. If you find yourself in trouble, you can also pull the emergency brake (the yellow diamond on the dashboard) to release air pressure. This will allow the springs to take over and stop the truck entirely. And if any part of the air brake system leaks, you can replace that piece alone knowing the rest of the system will continue to function as intended. Additionally, if the pressure drops below 45 psi, the air brakes will activate automatically and bring your truck to a safe stop.

In contrast, if any piece of a hydraulic system were to spring a leak (or if the lines are opened at all), the entire system would have to be flushed out and the affected line would need to be replaced.

When and Where to Replace the Brakes on Your Semi Truck

Brakes on a semi truck need to be replaced on average between 400,000 – 500,000 kms (or 250,000 – 300,000 miles). While replacing your brakes can be pricy, it is an absolutely necessary step for keeping your truck safe. Each axle can cost between $300 – $500 CAD, or $250 – $400 USD, running you anywhere from $1,800 – $3,000 CAD or $1,500 – $2,400 USD total.

When you’re ready to replace your brakes, any local truck repair shop should be able to help. We recommend reading and comparing Google reviews to find the most reputable shop in your area.

How to Care for and Extend the Life of Your Brakes

How and when you apply pressure to your brakes can affect their longevity, so it’s important to understand how exactly that works to keep them functional and safe for as long as possible.

Constant braking creates heat, which big trucks are designed to withstand. However, over time heat will increase the distance to the brake shoes and weaken their effect overall. Take your foot off the gas to slow yourself down long before you have to stop, and apply the brakes only when necessary.

When driving downhill, push down on the brake intermittently to allow the brakes to cool slightly in between. For example, if you can safely travel downhill at 50 miles an hour, press on the brake until you reach 45 miles an hour and release. Allow yourself to speed up to 50 again and repeat the process until you reach the bottom of the hill.

We also recommend checking your parking brake daily for broken or damaged pieces and ensuring there are no leaks in the chamber.

Ultimately, if you care for your brakes, they will care for you. Use this as a guide and return home safe after every trip.

If you are looking for buying pre-owned trucks, trailers, and semi-trucks in Winnipeg, contact Aspen Truck Sales today. We also offer truck leasing and carry reputed brands like FreightlinerVolvo, and others.