Technology File - Environmental Technology Here we present our environmental technology through illustrations and photographs.

Technology File - Safety Technology

Electrical 4WD System (E-Four)

Toyota First1

The newly developed, high performance, compact HV4WD for compact hybrid vehicles.

Unlike a mechanical 4WD system, the electrical 4WD system (E-Four) does not link the front and rear wheels with a propeller shaft, instead connecting them electrically, driving the rear wheels with motors instead of the engine. Large hybrid vehicles such as minivans use a high output E-Four system, but for the new (2015) Prius we have developed a new, compact HV4WD system for compact hybrid vehicles. It identifies when 4WD driving is needed during day-to-day use and automatically switches between front-wheel drive and four-wheel drive based on driving conditions, contributing to greater fuel efficiency.

  1. As of February 2017.
Electrical 4WD System (E-Four)

Our goal: The high fuel efficiency of a 2WD vehicle.

New (2015) Prius models with HV4WD (E-Four) achieve a JC08 test-drive mode drive fuel economy rate of 34.0 km/L. This fuel efficiency exceeds even that of the third-generation Prius 2WD vehicles (32.6 km/L). The new Prius has been carefully designed to offer excellent fuel efficiency through the use of numerous drag reduction technologies.

Fuel economy rates were determined under defined test conditions. Actual fuel economy rates may vary depending on customer usage environments (weather, traffic conditions, etc.) and driving conditions (sudden acceleration, air conditioner usage, etc.).

Our goal: The high fuel efficiency of a 2WD vehicle.

Repeated driving tests on the snowy roads of Tohoku and Hokkaido.

The new (2015) Prius has undergone numerous driving tests in Tohoku and Hokkaido, areas with heavy snows, to ensure that it can drive smoothly in wheel tracks, on slopes, in parking lots, over manholes, and in other areas in which driving is difficult on snowy roads. This testing has confirmed that the new Prius offers sufficient performance for regular daily use. The reliability of its systems has been improved through thorough, intensive driving in Hokkaido.

Repeated driving tests on the snowy roads of Tohoku and Hokkaido.

The same spacious luggage area as found in 2WD vehicles.

The HV4WD system unit is compact, roughly 75%2 lighter and smaller than the high output E-Four system. This makes it possible for the new (2015) Prius to offer almost the same amount of luggage space as a 2WD vehicle.

  1. Internal measurement value.
High output E-Four/ Roughly 75% more compact

Back to index

Specifications may differ depending on country, region, or model.