Toyota's original equipment manufacturer (OEM) engine parts are designed strictly according to the vehicle's technical specifications. For example, engine parts for models like the Corolla and Highlander must match specific physical parameters such as displacement, bore, and stroke, while also being compatible with the original vehicle's electronic control system communication protocols (such as CAN bus). Taking a brake booster as an example, its piston stroke and hydraulic output pressure must match the original vehicle's brake line pressure range; otherwise, it may lead to increased braking distance or abnormal pedal feedback.
The materials used in OEM parts (such as aluminum alloy cylinder blocks and high-strength steel gears) also undergo durability testing to ensure stable performance under extreme conditions (such as high temperature and high load).