production ceased in 1996. A single belt (serpentine belt) accessory drive was introduced on the L05, the 5.0L L03 and the 4.3L V6 LB4 engines used in the 1988 GMT400 models but not on the older R/V models (R/V models received the serpentine belt drive in 1989 when the front grille was facelifted in appearance to the GMT400 lineup). In mid-1996 the L05 was equipped with heads used in the 1996 G30. In February 2008, a Wisconsin businessman reported that his 1991 Chevrolet C1500 pickup had logged over 1 million miles without any major repairs to its L05 engine. (Source: The Flint Journal, February 17, 2008) The article also mentioned that the Flint engine plant that built the engine, had produced 45 million engines in its 45-year history, before closing in 1999. L31 The Vortec 5700 L31 (VIN code 8th digit "R") is a 5.7L V8 truck engine. It is Chevrolet's last production Generation I small-block. The cylinder heads feature combustion chambers and intake ports very similar to those of the LT1 V8, but lacking the LT1's reverse-flow cooling and higher compression. As such, the L31 head is compatible with all older small-blocks, and is a very popular upgrade. It offers the airflow of more expensive heads, at a much lower cost. It does, however, require a specific intake manifold (A 5.7L, 350 CI L31, Vortec engine has eight bolts attaching the intake manifold or four per head, as opposed to the "traditional" six bolts per head; twelve in total found on older Chevrolet small blocks). Chevrolet's L31 was replaced by GM's 5.3L LM7 V8. The Vortec 5700 produces to at 4,600 RPM and to of torque at 2,800 RpM. Known as the GEN 1+, the final incarnation of the 1954 era-vintage small block ended production in 2005 with the last vehicle being a Kodiak/Topkick HD truck. It is still in current production as a crate engine for marine applications and automotive hobbyists as the 'RamJet 350' with minor modifications. Volvo Penta and Mercury Marine also still produce the L31. The "Marine" intake, despite its cast iron construction, is an L31 upgrade that allows use of common Bosch-style injectors with various flow rates while still maintaining emission compliance. 1996–1999 Chevrolet/GMC C/K full-size trucks 1996–1999 Chevrolet Suburban/GMC Suburban full-size long-wheelbase SUVs 1996–2000 Chevrolet Tahoe/GMC Yukon (and 2000 Tahoe Limited, 2000 Tahoe Z71, 2000–mid-2003 Sonora models) full-size short-wheelbase SUVs 1999–2000 Cadillac Escalade