1HDT

The 1HDT is a 4.2-liter, 24-valve, turbocharged direct-injection diesel engine manufactured by Toyota. It is a member of Toyota's HD series of diesel engines and is known for its robust construction and reliability. The 1HDT features a cast-iron block and cylinder head, overhead camshafts, and a turbocharger for enhanced power output and efficiency.

This engine was commonly found in Toyota Land Cruiser models, particularly the 80-series and 100-series, from the early 1990s through the early 2000s. It was also used in some Toyota Coaster buses. The 1HDT is highly regarded by off-road enthusiasts and owners of older Land Cruisers for its durability and its ability to handle demanding conditions.

Key features of the 1HDT include its direct injection fuel system, which contributes to better fuel economy compared to indirect injection systems. The turbocharger provides a significant boost in torque, making it well-suited for towing and carrying heavy loads. While not known for high horsepower figures by modern standards, its strong low-end torque and overall longevity have made it a popular choice for those seeking a dependable and capable diesel powertrain. Maintenance is generally straightforward, and parts are widely available, further contributing to its enduring appeal.