Common Problems that Cause Semi Trucks to Break Down

Billy Bob’s Repair & Tire • 31 October 2025

For long-haul truckers and fleet operators, keeping semi trucks in good working condition is essential for safety and profit. When a truck breaks down, it can lead to missed deliveries and long stretches of downtime. While regular maintenance can prevent many issues, certain mechanical and electrical problems are especially common in heavy-duty trucks that log thousands of miles each month. At Billy Bob’s Repair & Tire, we provide 24/7 roadside semi truck repair in the greater San Antonio, TX area. Here are four common reasons that semi trucks break down.


Engine Trouble

Engine failure is one of the leading causes of roadside breakdowns for semi trucks. Over time, engines endure tremendous stress from hauling heavy loads and operating for long hours in demanding conditions. Common causes of engine trouble include overheating, oil leaks, worn belts, and injector problems. When a semi’s engine begins to lose power, make knocking noises, or emit excessive smoke, it’s a clear sign that immediate attention is needed. 


Electrical System Failures

Semi trucks rely heavily on complex electrical systems to power everything from the lights to electronic control modules. When electrical issues arise, they can cause major disruptions. Dead batteries, loose wiring, corroded connections, and failing alternators are common culprits behind electrical failures. Drivers should have their electrical systems checked regularly, especially before long trips, to reduce the risk of roadside breakdowns.


Brake Problems

A truck’s braking system is crucial for safety, and any failure can be catastrophic. Because semi trucks use air brakes, even small leaks can lead to decreased braking efficiency or even failure. Regular inspections of air lines, brake shoes, and compressors can prevent these dangerous problems and help ensure dependable stopping power under all conditions.


Tire and Wheel Issues

Tires are among the most frequently replaced components on a semi truck, and for good reason. Blowouts, uneven wear, and tread separation are all common problems that can lead to breakdowns or accidents. Overloaded trailers, improper inflation, and alignment problems accelerate tire wear. Regular inspections and proper tire maintenance help prevent these issues.


24/7 Mobile Semi Truck Repair in San Antonio, TX

For expert roadside mobile semi truck repair in San Antonio and the surrounding area, contact Billy Bob’s Repair & Tire at (210) 796-3891. Feel free to give us a call and we’ll arrive ASAP to get you back on the road!