Empezado por JPVM
Overview
Truck buyers choose the Vortec 5.3L more frequently than any of GM Powertrain’s Vortec V8 engines, and the reasons aren’t hard to discern. This was one of the first truck V8s to offer full E85 flex-fuel capability. It was the foundation for Powertrain’s innovative Parallel Hybrid Technology and powers the first hybrid pickups in the marketplace. The Vortec 5.3L Gen III V8s deliver a near-perfect balance of torque, free-breathing horsepower, fuel efficiency, low maintenance and low cost of ownership. They precisely suit the needs of working truck owners and vehicle platform teams alike.
Introduced in the 1999 Chevrolet Silverado and GMC Sierra, the first Vortec 5.3L V8 (RPO LM7) was developed in the tradition of the original Chevrolet small block using the latest, best overhead-valve technology available. Like all Gen III Vortecs, it introduced a lighter valvetrain that reduced friction and increased efficiency. A steel camshaft reduced mass while maintaining truck-grade durability. Steel roller rockers added stiffness, allowing greater engine speed with less vibration. Hydraulic roller lifters reduced friction for better fuel economy and wear resistance. The Vortec 5.3Ls share their engine block and, in most cases their cylinder heads, with the Gen III Vortec 4.8L (LR4). The 5.3Ls have nine mm greater stroke for an additional 520 cubic centimeters displacement.
The LM7 was flexible enough, and sophisticated enough, that five years after its launch it provided the internal-combustion power for the Chevrolet Silverado and GMC Sierra Hybrids. These trucks deliver the highest city fuel mileage of any full-size pickups, not to mention an on-board electrical generator that can power a job site, a camp site or a household, in the event of a power outage.
In 2002, GM Powertrain launched RPO L59--the first flexible-fuel V8 for full-size sport-utility vehicles. The 5.3L LM4—the first all-aluminum Vortec V8—followed a year later. Continuous improvement has been the guiding principal for all of the Vortec 5.3Ls. Since launch, virtually every component or system has been reviewed to increase value for the customer: management electronics, NVH control, materials, build tolerances, performance and efficiency have been enhanced annually, all with an eye toward conserving valuable resources and protecting the environment. Even required maintenance has been reduced. The industry’s best oil-monitor system records engine temperature, length of operation at a given temperature and several other operating parameters, then indicates an oil change when it's actually needed, rather than according to a predetermined interval. The standard spark plugs extend anticipated plug life to 100,000 miles, as do extended-life accessory belts. The coolant maintains its cooling and corrosion-inhibiting properties for 150,000 miles. Scheduled maintenance is limited to oil changes.
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