Toyota only offers a diesel option for its full-size Tundra pickups. The Tundra features a Cummins 5.0-liter turbo diesel V8 engine. Despite other manufacturers offering diesel options on their midsize trucks, Toyota has decided not to include one for its midsize Tacoma pickups.
Toyota decided not to offer a diesel Tacoma based on the significant raise in the price of the vehicle if a diesel system was added. Advantages of diesel engines included improved fuel economy, generally performing 25 to 30 percent better than gasoline engines. While having their advantages, EPA regulations have made diesel engines more expensive to build. These factors weigh into the vehicle manufacturer's decision when decided whether to include a diesel option.