The superior performance of high-mileage electric cars is largely attributed to the relative simplicity of their powertrains. A traditional internal combustion engine consists of thousands of moving parts, including pistons, valves, fuel injectors, and complex exhaust systems, all of which are subject to heat, friction, and vibration over time. These components require precise lubrication and cooling, and as they age, the likelihood of a failure in one of these systems—such as an emissions leak, a fuel system fault, or a transmission issue—increases. Electric vehicles, by comparison, have significantly fewer moving parts. The absence of a traditional multi-speed gearbox, a complex exhaust treatment system, and the various belts and pumps associated with petrol engines appears to result in a more robust vehicle over the long term.
However, the study was not entirely a clean sweep for electric vehicles. While they excelled in overall mechanical durability and drivetrain reliability, the data highlighted specific areas where EVs are currently less durable than petrol cars. Most notably, the analysis found that across the entire dataset, electric vehicles recorded approximately 1.8 times as many tyre-related defects as petrol cars. This finding aligns with long-held observations from automotive experts regarding the unique stresses that electric cars place on their rubber.
The increased rate of tyre wear in electric vehicles is generally attributed to two primary factors: weight and torque. Because of the heavy battery packs required to provide competitive range, electric vehicles often weigh significantly more than petrol cars of a similar size. This additional mass puts greater constant pressure on the tyres. Furthermore, electric motors deliver maximum torque instantly from a standstill, which can lead to more aggressive wear during acceleration compared to the more gradual power delivery of a petrol engine. The MOT data suggests that while EV owners may save money on engine repairs, they are likely to face more frequent expenses related to tyre maintenance and replacement.
Interestingly, the study also shed light on the performance of hybrid vehicles, which utilize both an internal combustion engine and an electric motor. Despite the perceived complexity of having two separate power systems, hybrids performed exceptionally well in the analysis. In several categories, hybrid cars recorded lower MOT failure rates than both pure petrol cars and fully electric vehicles. This suggests that the hybrid market has matured to a point where the systems are highly refined, or perhaps that hybrid drivers tend to have driving patterns that are particularly conducive to maintaining vehicle health.
