A semi-truck driver carries a lot of responsibility—not only to deliver the contents of their trailer on time but also to make sure their vehicle isn’t a safety hazard on the road. Even if you have a mechanic look over the vehicle before each trip, it’s up to you to be able to recognize potential problems. The guide below looks at common issues affecting semi-truck brakes, in particular, so you can address them before they present a danger to yourself or others.

Warning Signs of Brake Failure

1. Misaligned Brake Shoes

Brake shoes come in pairs that are meant to wear out evenly. However, if one becomes thinner ahead of the other, it will cause an imbalance that stresses the weaker shoe further. Its lining will begin to rub against the wall of the brake drum, creating worrisome friction. Therefore, see a mechanic if there is abnormal scraping or squeaking noises when the pedal is depressed or if the truck is less responsive to braking than normal. 

2. Damaged Airline

You may also need truck service if your truck’s airline becomes damaged. Unlike passenger vehicles, semi-trucks use air via a pneumatic system to power the brakes. When an airline breaks, cracks, or gets punctured, the air pressure is compromised, preventing you from stopping as effectively.

3. Bad Compressor

mechanicEvery semi-truck has an air compressor that fills a reservoir with air, which the airlines deliver to the brakes as needed. This system is necessary for building up the appropriate levels of pressure. If you’re not getting enough air to the brakes and there isn’t damage to the airlines, you may need to take the vehicle to a truck repair shop to have the compressor tested.

4. Brake Lock 

You may also need a mechanic if you experience a stuck brake shoe. While the semi-truck may halt properly when needed, the vehicle may seem sluggish when you begin to accelerate again. This is often because the brake shoe is struggling to release itself.


Stephenson Truck Repair in Lincoln, NE, is a full-service repair and body shop for RVs and commercial vehicles. Whether you need a mechanic to check out the brakes or to help restore it after a collision, these experienced technicians know what to do. Browse their services on their website or call (402) 466-8532 to arrange for service.