The 2026 Summer Breakdown Index: The U.S. Cities Where Summer Heat Hits Cars Hardest

As temperatures climb, summer heat places added stress on key vehicle systems, like the battery, cooling system, and A/C components. Based on exclusive Pep Boys internal service data, the report identifies where drivers are most likely to need repairs tied to extreme summer conditions, including air conditioning repairs and battery replacements.

Based on exclusive Pep Boys internal service data, the report identifies where drivers are most likely to need repairs tied to extreme summer conditions, including air conditioning repairs and battery replacements.

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Top 15 Cities in the Summer Breakdown Index

Based on our internal service data indexing rates of air conditioning repairs and battery replacements during peak summer months (May-August), below are the top 15 metro areas for summer vehicle stress:

Las Vegas, NV
Orlando, FL
San Antonio, TX
Lubbock, TX
El Paso, TX
Jacksonville, FL
Austin, TX
Phoenix, AZ
Tucson, AZ
Yuma, AZ
Salt Lake City, UT
Nashville, TN
Tallahassee, FL
Houston, TX
Bakersfield, CA

While the cities span different regions of the country, they share one common challenge: conditions that placed added strain on vehicle systems responsible for keeping drivers comfortable and helping prevent overheating.

In our analysis, we also found some unique trends:

Las Vegas ranks #1 for summer A/C stress, with drivers experiencing air conditioning repairs at more than three times the Pep Boys average during peak summer months.
Tucson leads all markets in summer battery replacements, highlighting how extreme heat can shorten battery life and trigger unexpected failures.
Lubbock emerges as the most repair-intensive summer market, showing the highest overall rate of heat-related the vehicle services compared to the national Pep Boys baseline.
Orlando records the highest overall summer service volume, underscoring how common heat-related vehicle issues become in peak travel destinations.
11 of the 15 top summer service markets are concentrated in the Southwest, with no Northern or Midwestern metros appearing in the highest-risk rankings.
30% of the summer breakdown markets are located in Texas, reinforcing the state’s position as a hotspot for prolonged heat-related vehicle strain.
Arizona accounts for 20% of the highest-index markets, with desert-heat cities like Phoenix, Tucson, and Yuma standing out for elevated battery replacement activity.

Why Summer Heat is So Hard on Vehicles

High temperatures accelerate wear and can increase the risk of overheating, weak battery performance, and reduced air conditioning efficiency.

Why Cooling System Failures Can Escalate Quickly

Cooling system problems can cause engine temperatures to spike fast. If left unchecked, overheating can damage major components.

Why Summer Heat Drains Batteries Faster

Heat speeds up battery fluid evaporation: When the temperature rises, the liquid inside your battery evaporates faster, which can damage internal components.
High temperatures increase corrosion: Heat can accelerate the chemical reaction in your battery, leading to corrosion on terminals and reduced performance.
Your battery works harder in the summer: Air conditioning, fans, and electronics all put extra load on the battery when temperatures soar.

How Extreme Heat Stresses Your A/C System

Your car’s A/C doesn’t just cool the air – it removes humidity too.

That’s why it helps defog your windows so quickly, even in the winter.

How to Reduce Your Risk of a Summer Breakdown

While no vehicle is immune to extreme temperatures, regular maintenance can help reduce the likelihood of a breakdown.

Before summer travel season, consider:

Testing your battery
Inspecting your air conditioning system
Checking coolant levels and condition
Looking for signs of leaks
Inspecting belts and hoses
Scheduling an oil change, brake inspection, and/or tire rotation before long road trips, which comes with a FREE Pep Check at Pep Boys

Preventive maintenance can be far less expensive, and far less stressful, than dealing with a breakdown on the side of the road.

What the Summer Breakdown Index Tells Us

The Summer Breakdown Index highlights a simple reality: heat can be just as tough on vehicles as cold weather.

Whether it’s a weakened battery, or a stressed cooling system, summer conditions can create challenges for drivers across the country.

By understanding how heat can affect your vehicle and staying proactive with maintenance, you can reduce the risk of unexpected repairs and enjoy a more reliable driving experience throughout the summer.

If you’re planning a road trip or simply want peace of mind before temperatures climb even higher, considering scheduling a service at Pep Boys today.