The GS 400 is powered by a 4.0-liter V8 engine known as the 1UZ-FE. In North American models, this engine produced roughly 290 horsepower, delivering a smooth and confident drive that matched the GS’s luxury-sport positioning during its era.
Engine lineage and core specs
The following section lists the essential technical details that define the GS 400's powertrain.
- Displacement: 4.0 L (3997 cc)
- Configuration: 90-degree V8
- Valvetrain: DOHC with 32 valves
- Block material: Aluminum
- Induction: Naturally aspirated with electronic fuel injection
- Power output: Approximately 290 horsepower (varies by market and year)
The 1UZ-FE is known for its refined delivery, durability, and a balance of performance with the luxury DNA that defined the GS line in the late 1990s.
Market years and variations
There were regional differences in tuning and equipment, but the GS 400 widely shared the 4.0-liter 1UZ-FE V8 as its core engine across most markets and model years in which the variant was offered.
Additional context on the engine family
The GS 400’s engine belonged to the same 1UZ-FE family used in other Lexus luxury models of that era, such as the LS 400 and SC 400. This shared powertrain approach underscored Lexus’ emphasis on reliability, refinement, and smooth power delivery across its flagship sedans and coupes.
Summary
In short, the Lexus GS 400 runs on the 4.0-liter 1UZ-FE V8. It delivers a balance of strong power and refined performance that complemented the model’s positioning as a premium, sport-oriented sedan in the late 1990s.