Chevrolet LS4 Engine Specs

The Chevrolet LS4 is a naturally aspirated OHV V8 petrol engine produced from 2005 to 2009, a distinctive member of GM's LS small-block family engineered specifically for transverse, front-wheel-drive applications - an unusual configuration for a pushrod V8, which are almost always installed longitudinally in rear-wheel-drive vehicles. It was used in the Chevrolet Impala SS and Monte Carlo SS, as well as the Pontiac Grand Prix GXP and Buick LaCrosse Super, giving front-wheel-drive family sedans genuine V8 performance for a brief period in the mid-2000s.

Producing 303hp and 438Nm of torque from 5,327cc, the LS4 shares the broader LS family's deep-skirt aluminum block and OHV 16-valve architecture, but with a shortened front accessory drive and a specifically engineered bellhousing pattern to mate with GM's 4T65E-HD front-wheel-drive automatic transmission - a considerably more complex engineering exercise than simply installing an LS engine in its native rear-wheel-drive orientation.

Because the LS4 is a comparatively rare, purpose-built variant rather than a mainstream LS engine, several practical considerations set it apart from more common LS family members. Some transmission-specific and front-wheel-drive-specific accessory parts can be more difficult to source than parts for the mainstream rear-wheel-drive LS engines, since the LS4 was produced in relatively limited numbers and for a shorter production run. The 4T65E-HD transmission it's paired with is a known stress point in these applications, given the demands of transmitting V8 torque through a front-wheel-drive transaxle design not originally conceived for this much power; transmission health and maintenance history are worth scrutinizing carefully on any used example. The core engine itself benefits from the same fundamental LS-family reliability and reasonably strong tuning potential as its more common siblings, though the front-wheel-drive-specific engineering means most of the vast LS aftermarket parts catalog isn't directly compatible without adaptation. General LS-family maintenance items - gasket condition, timing chain wear at higher mileage - apply equally here.