In 2023, there were 286 million vehicles registered to run on U.S. roads. The average age of those vehicles was 12.6 years, a record high for the nation. Older vehicles are much more likely to break down due to a combination of mechanical wear and tear, outdated parts, and neglected maintenance. Additionally, as cars age, critical components like the battery, alternator, cooling system, and tires naturally degrade (especially after the 10-year mark).
In the U.S., there are millions of car breakdowns every year. According to the AAA, there are over 8 million roadside assistance calls every summer and winter, and slightly less than 8 million each fall and spring.
This study will dig into the details around particular reasons for breakdowns, and look at how to avoid such issues, with the key problem – aging cars – as the primary focus.
A Closer Look At Car Age On U.S. Roads
This vehicle year model percentage table clearly illustrates an aging U.S. vehicle fleet. Older vehicles are surprisingly common: 44% of cars on the road are models from 2014 or earlier.
Vehicles from 2015–2019 represent the largest share at 26%, indicating a surge in purchases during that period, likely driven by post-recession recovery and pre-pandemic buying trends.
The newest vehicles (2020 to 2024) make up just 12% of the total fleet, which reflects both pandemic-era supply chain disruptions and inflated prices stymying new car sales.
Such a large share of older vehicles suggests ongoing demand for repairs, parts, and roadside assistance services, with aging cars far more prone to mechanical failures.
It also hints at significant economic factors, such as inflation, high interest rates, and the rising cost of new vehicles, all of which encourage drivers to maintain their older cars, rather than buy a new one. Overall, the data shows a road network where older, breakdown-prone cars share space with a slowly growing and modest proportion of newer, technologically advanced models.
AAA data tells us that vehicles aged 10 years or older account for over two-thirds of all roadside assistance calls, and that 81% of the vehicles that were towed to a repair shop were at least a decade old, underscoring the higher breakdown risk that comes with aging cars.
With 69 million vehicle breakdowns in total each year in the U.S. (or 189,000 every day, affecting one in three motorists), the costs are significant – an annual $44 billion. And cars over a decade old are twice as likely as newer models to experience a breakdown (and four times more likely to require towing).
Breakdown Methodology
Our vehicle age analysis uses 2023 data covering 286 million U.S.-registered vehicles, with 44% aged 10 years or older and 56% aged less than 10 years. As older vehicles are twice as likely as newer models to break down, we applied a weighted formula to estimate how the 69 million annual breakdowns are distributed across the total fleet.
By assigning a breakdown rate of x to newer vehicles and 2x to older ones, we solved the equation in the following way: 69 million = (160.16 million × x) + (125.84 million × 2x), resulting in x ≈ 0.1676.
This calculation estimates that older vehicles account for approximately 42.2 million breakdowns per year, or 61% of the total, despite comprising less than half of the fleet. And although older cars are more susceptible to failure, breakdowns are usually due to a very specific factor.
Specific Breakdown Factors and Vehicle Maintenance
30% of vehicle breakdowns are caused by a faulty battery (vehicle batteries typically last five years or so before they need to be replaced). That said, if you don’t drive your vehicle very often, or if you only cover short distances, you may need to replace your battery within five years.
11% of vehicle breakdowns are caused by cooling system failures. Cooling system parts like the radiator, the water pump, and the thermostat can abruptly fail, which can subsequently lead to an overheated engine. One early warning sign is fluid pooling beneath the vehicle when it’s parked, which could well indicate a coolant leak.
Approximately 82,000 crashes every year are due to tire incidents, including blowouts, flats, and failures. Hitting debris or potholes can harm your tires, but most tire issues stem from a lack of maintenance.
To stay safe on the road, you should make sure your tires are properly inflated and that they retain a tread depth of at least 1.6mm. Regardless of how much you drive, you should be looking to replace your tires every six years to avoid wear-related breakdowns.
Consistent maintenance of a vehicle is one of the best defenses against unexpected roadside failures, yet many drivers fail in this regard. A 2022 AAA survey found that 35% of U.S. motorists postpone or skip recommended services, often due to budget constraints, time pressures, or a belief that the work isn’t urgent. That can mean an unexpected breakdown – especially if you’re driving a lot of miles over the summer.
Seasonal Breakdown Factors
Summer is the season for potential vehicle breakdowns due to extreme heat, an increased number of vehicles on the road, and the stress placed on your vehicle’s cooling system. AAA reports 8.3 million breakdown calls during the summer months.
Just behind summer, winter is the second-worst month for vehicle breakdowns, with 8.1 million call-outs. Colder temperatures increase battery wear, thicken engine oil, and complicate fluid performance, which can cause older or poorly maintained vehicles to malfunction.
Fall sees 7.8 million AAA calls, with spring subject to 7.7 million. During transitional periods, milder weather may slightly reduce mechanical stress. Yet the transition to spring may mean increased lockouts and battery problems after long storage periods or a stretch of winter inactivity.
Industry data from roadside assistance provider Agero shows that the third quarter (July to September) spans the peak travel season (which features 27% of all annual roadside breakdowns), while the first quarter (January to March) sees the fewest breakdowns (23%). This aligns with a summer spike and a winter lull, and highlights how concentrated breakdowns are during late summer.
Vehicle Recalls
Vehicle recalls can be a significant factor when it comes to roadside breakdowns, especially when they involve essential mechanical or electrical systems. In 2023, the National Highway Traffic Safety Administration (NHTSA) reported more than 1,000 recalls, which affected over 32 million vehicles.
Many of these recalls were due to issues with fuel systems, braking components, steering mechanisms, and engine controls. If these issues are not repaired, they can lead to sudden stalling, loss of power, or other serious failures.
While manufacturers repair recalled defects at no cost, NHTSA data shows that nearly one in four recalled vehicles remain unrepaired, which leaves millions of drivers vulnerable to unresolved safety risks. If we combine this factor with the nation’s aging vehicle fleet, it’s clear that unrepaired recalls contribute to a significant share of breakdowns and roadside emergencies each year.
The above table reveals the ten vehicle brands with the highest number of recalls in 2023, highlighting the manufacturers most frequently affected by safety or defect issues. Ford Motor Company leads by a significant margin with 58 recalls (16% of the total), followed by Chrysler at 45 recalls (13%).
Premium brands like BMW (32 recalls) and Mercedes-Benz (31 recalls) also prominently feature, each representing 9% of the total. Major U.S. manufacturers such as General Motors (25 recalls, 7%) and Nissan (23 recalls, 6%) feature alongside Daimler Trucks, Kia, Jaguar Land Rover, and Volkswagen, the latter four each holding a 6% share and recalling between 21 and 23 vehicles.
The presence of both mass-market and luxury brands on the top ten recalls list shows that recalls are not price-point related. The brand spread also confirms that a relatively small cross-section of manufacturers account for a disproportionate number of all recalls, with Ford and Chrysler together responsible for nearly 30% of the total.
The Road Ahead
In 2023, the 286 million registered vehicles on U.S. roads were the oldest on record, with an average age of 12.6 years. Nearly 44% of these vehicles were models from the year 2014 or earlier, reflecting a national trend to retain cars for longer periods due to inflation, high interest rates, and rising new vehicle prices.
This aging fleet is a major reason for so many mechanical failures, with AAA data confirming that vehicles over 10 years old account for more than two-thirds of all roadside assistance calls, and a staggering 81% of towed vehicles.
Nationwide, drivers experience 69 million breakdowns annually (189,000 a day), which costs Americans $44 billion a year. Breakdown incidents disproportionately affect older vehicles, which are twice as likely to break down and four times more likely to be towed, compared to newer counterparts.
Mechanical wear plays a critical role, with battery issues causing 30% of breakdowns and cooling system failures responsible for 11%. Poor tire maintenance leads to approximately 82,000 crashes per year, often due to either underinflation or aging rubber, issues easy to prevent with routine inspections or timely tire replacements.
Seasonal weather also compounds risk, with summer being the main breakdown season due to heat-related stress on cooling systems and batteries.
The AAA fielded 8.3 million service calls during the summer, followed closely by 8.1 million in winter, when cold weather strains vehicle fluids and weak batteries. Fall and spring bring slightly fewer incidents (7.8 and 7.7 million calls, respectively) but still feature an enormous number of breakdowns, with a significant percentage of failing vehicles emerging from seasonal storage.
Nationwide, drivers experience 69 million breakdowns annually (189,000 a day), which costs Americans $44 billion a year
As well as aging components, vehicle recalls also compound breakdown risk. In 2023 alone, the NHTSA issued over 1,000 recalls, amounting to more than 32 million recalled vehicles.
Many recalls involved critical systems such as brakes, steering, or fuel delivery, all of which can cause on-road failures if unaddressed. And because 1 in 4 of recalled vehicles are not fully repaired, millions of drivers face unresolved, unpredictable safety risks – and potentially imminent breakdown. Brands like Ford and Chrysler led the list of recalls, together responsible for nearly 30% of all cases.
Despite the risks outlined in this study, preventive maintenance should not be underestimated. AAA data shows that 35% of U.S. drivers skip or delay routine service, exacerbating older vehicle vulnerability. By regularly changing the battery or tires, a vehicle owner can massively improve their odds of avoiding a breakdown.
A lack of general vehicle upkeep, plus neglectful recall habits and environmental stressors, continues to create a perfect storm of breakdown risks that will continue to afflict millions of U.S. drivers every year.
Here at Therman Law Offices, we have over 35 years of experience and can develop a strategy tailored to your specific needs and circumstances. Whatever your issue, get in touch today to find out how we can help.
