Gen III & Gen IV Vortec truck engines
Although performance car engines have typically carried “LS” designations, truck engines built on this platform have been dubbed Vortec. In the beginning, they were generally distinguished by iron cylinder blocks and were offered in smaller displacements than car engines. Interestingly, a 5.7L Vortec “LS” engine has never been offered. Here’s a quick rundown of the previous and current-production LS truck engines:
* 4.8L – The smallest-displacement LS engine (293 cu in); it uses an iron block with 3.78-inch bores and aluminum heads.
* 5.3L – The most common LS truck engine (327 cu in), it uses the same iron block with 3.78-inch bores as the 4.8L, but with a longer stroke , (3.62-inch)crank. Later versions equipped for Active Fuel Management. Manufactured with iron and aluminum cylinder blocks.
* 6.0L – Used primarily in 3/4-ton and 1-ton trucks, the 6.0L (364 cu in) uses an iron block (LY6) or aluminum block (L76) and aluminum heads, with provisions for Active Fuel Management; some equipped with variable valve timing.
* 6.2L – Commonly referred to by its L92 engine code, the 6.2L (376 cu in) engine uses an aluminum block and heads, and incorporates advanced technology including variable valve timing. The L92 is used primarily as a high-performance engine for the Cadillac Escalade and GMC Yukon Denali.