The 4.8 L and the 5.3 L are smaller truck versions of the LS1 and were designed to replace the 305 and the 350 in trucks. Both the 4.8 L and the 5.3 L share the same engine block, heads (upper end) and as they share architecture, parts interchange freely between these engines and other variants in the LS family.
The Vortec 4800 LR4 (VIN code "V") is a Generation III small block V8 truck engine. Displacement is 4.8 L (293 cu in) with a 96.01 mm (3.78 inch) bore and 83 mm (3.27 inch) stroke. It is the smallest of the Generation III Vortec truck engines and was the replacement for the 5.0 L 5000 L30.
- The LR4 engines from 1999-2000 produced 255 hp (190 kW)
- The 2001 and above models made 270–285 hp (201–213 kW)
- All have a torque rating between 285–295 lb·ft (386–400 N·m), depending on the model year and application.
The 2005-2006 models made 285 hp (213 kW) and 295 lb·ft (400 N·m). They use flat top pistons.