Top Causes of Summer Semi Truck Breakdowns

Summer may be one of the busiest seasons for drivers, but it’s also one of the toughest on your truck. From overheating engines and tire blowouts to battery failures and air conditioning problems, high temperatures can place significant stress on your truck’s most critical components and systems. 

Fortunately, many of the most common summer truck breakdowns are preventable. Before summer gets too hot, here’s how you can prep your medium- and heavy-duty truck.

How to Prevent Summer Truck Breakdowns

Engine Overheating

Engine overheating is one of the top common causes of summer truck breakdowns. Your cooling system works overtime during hot weather to regulate your engine’s temperature. Even a minor issue can quickly result in severe engine damage.

Common causes of engine overheating include:

• Low coolant levels
• Coolant system leaks
• Faulty thermostat
• Damaged radiator hoses
• Failing water pumps
• Malfunctioning cooling fans
• Clogged radiators

If these issues are left unchecked, overheating can lead to warped engine components, or worse — complete engine failure.

How to Prevent Engine Overheating:

• Regularly check coolant levels
• Inspect hoses, clamps, and fittings for leaks or cracks
• Flush and replace coolant, according to manufacturer recommendations
• Clean the radiator of dirt, bugs, and road debris
• Test thermostat and cooling fan operation
• Schedule a professional cooling system inspection

Tire Blowouts

Heat creates a host of issues for your truck’s tires. For example, as pavement temperatures rise, heat can cause the air in your tires to expand, which can result in over inflation. Combined with worn tread, underinflation, and damaged sidewalls, the risk of blowouts and tire separation significantly increases during the summer months.

A tire blowout can create dangerous driving conditions and lead to costly roadside service or towing. When it comes to summer tire care, here’s what you should know.

How to Prevent Tire Blowouts:

• Check tire pressure during pre-trip inspections when tires are cool
  • Preferably in the morning before driving
• Follow manufacturer-recommended PSI guidelines
• Inspect tires for
  • Uneven wear
  • Low tread depth
  • Cuts and punctures
  • Cracks
  • Sidewall damage
• Rotate tires when needed
  • Typically every 50,000 miles or when they reach halfway through their treadlife
• Align and balance your tires at least once a year
  • Align every 80,000 to 100,000 miles
  • Balance every 15,000 to 20,000 miles
• Use a Tire Pressure Monitoring System (TPSM)

Proper tire inflation not only reduces the risk of blowouts but can improve fuel economy and overall vehicle safety.

Battery Failure

While battery problems are most commonly associated with winter, extreme heat can be even more damaging. There are several common causes of truck battery drainage during extreme summer heat, including:

• Weakened electrical connections caused by corroded terminals
• Interrupted charging due to loose or damaged battery cables
• Loss of performance from older batteries
• Improper charging from a faulty alternator
• Accessories and electronics can slowly drain the battery when the truck is off
• Vibration damage caused by loose battery mountings
• Long periods of idling or inactivity can put extra strain on the battery

If you need to replace your battery, check out our guide to semi truck battery types and replacement options.

Air Conditioning Malfunctions

When temperatures are high, the last thing you want is a malfunctioning air conditioning system. Skipping maintenance can lead to weak airflow, unexpected breakdowns, or even full A/C system failure. Common causes of A/C failure include:

• Refrigerant leaks
• Damaged hoses
• Worn compressors
• Dirty air cabin filters
• Faulty blower motors

Want to learn more about keeping your truck cool mile after mile? Check out our complete Truck A/C Maintenance Guide for more preventative maintenance tips.

Fluid Leaks

Summer heat accelerates vehicle fluid breakdown, thus exposing any existing leaks throughout the truck. Topping off or changing the oil and other fluids will help improve the effectiveness and function of your truck. Critical fluids to monitor include:

• Engine oil
• Coolant
• Transmission fluid
• Brake fluid
• Power steering fluid
• Windshield washer fluid

The recommended oil change interval varies from 10,000 to 35,000 miles, based on idle time. The higher the idle time, the more frequently you should change the oil. 

How to Prevent Fluid Leaks:

• Regularly check fluid levels
• Follow recommended fluid change intervals
• Look for signs of leaks beneath the truck
• Perform oil analysis when appropriate
• Address minor leaks before they lead to major repairs

Brake System Problems

Your brake systems work harder during the summer months, particularly when hauling heavy loads over long distances. Heat buildup can accelerate wear and affect braking performance.

To prevent brake system failures, inspect:

• Brake pads
• Brake shoes
• Rotors
• Drums
• Air brake components
• Brake fluid levels
• Air lines and connections

If you need replacement brake components, our parts department stocks a wide selection of commercial truck brake parts and maintenance components.

Fuel System Issues

High temperatures can affect fuel system performance and fuel economy. Leaks, clogged filters, and worn components can become more problematic during hot weather operations.

How to Prevent Fuel System Issues:

• Inspect fuel lines and fittings
• Replace fuel filters according to maintenance schedules
• Watch for signs of fuel leaks
• Address reduced performance or fuel economy concerns promptly

Fix Summer Breakdowns With These 7 Inspections

The best way to avoid costly summer breakdowns is through preventative maintenance. Identifying potential issues before they become emergencies can improve uptime, reduce repair costs, and keep your truck operating efficiently all season long.

Our expert technicians at Coopersburg Kenworth, Liberty Kenworth of South Jersey, and Liberty Kenworth of Bristol perform comprehensive seasonal inspections, preventative maintenance services, cooling system diagnostics, brake repairs, tire services, A/C repairs, and more.

Whether you operate a single truck or manage an entire fleet, our service teams are ready to help you prepare for the demands of summer driving. Schedule your summer maintenance appointment today and travel confidently and coolly.

Download the printable checklist at the top of this blog to help spot potential issues and how to prevent costly breakdowns before they happen.