L86 Vs. L87: What Is The Difference Between These Two Small Block Engines?

General Motors debuted the Gen 5 L86 6.2-liter EcoTec3 V8, one of the most reliable GM engines ever, in 2014 for use in various large SUV and full-size pickup truck applications. While similar to the 6.2L LT1 used in the C7 Corvette and sixth-gen Chevy Camaro, the L86 EcoTec3 featured longer intake manifold runners to achieve its peak 460 lb-ft of torque at 4,100 rpm. Peak power production of 420 horsepower occurred at 5,600 rpm, falling just 35 horsepower short of the performance-oriented LT1.

The 6.2L L86 EcoTec3 featured cast aluminum engine block and cylinder head construction with an overhead valve layout consisting of two valves per cylinder and variable valve timing. Ignition spark came from individual coils located near each platinum-tipped spark plug fed by low-resistance spark plug wires. Direct fuel injection supplied fuel to each cylinder, metered by GM's Active Fuel Management system for increased fuel efficiency. Internally, a two-stage oil pump supplied pressurized oil to lubricate engine components as well as the oil-jet piston cooling system.

The L87 version of the 6.2-liter V8, also regarded as one of the best engines ever put in a Chevy truck, came out in 2019 as the successor to the L86. It features many of the best aspects of the L86 and adds some key features to improve efficiency and reliability, such as its Automatic Start/Stop capability and available Dynamic Fuel Management system (DFM).

The most significant advantage the L87 EcoTec3 holds over its L86 precursor is improved fuel efficiency technologies. According to EPA-estimates, a 2014 Chevrolet Silverado equipped with the L86 6.2L and a six-speed automatic transmission gets 14 mpg in the city, whereas a 2019 Silverado with the L87 6.2L and a 10-speed automatic gets an estimated 16 mpg in the city. It's interesting that both trucks get an estimated 20 mpg on the highway and a 17-mpg combined rating. While the ten-speed transmission provides some benefits to the 2019's city fuel economy, the Automatic Start/Stop and technologically-advanced DFM system add efficiency as well, especially during city driving conditions.

The AFM system found in the L86 6.2L EcoTec3 deactivates four of the eight cylinders to save fuel when driving conditions require less power. The L87 improves upon that system with DFM which "operates in multiple cylinder deactivation patterns" to increase efficiency, according to GM Powered Solutions. Finally, the Automatic Start/Stop feature used on the L87 reduces engine idling anytime the truck is stopped in traffic, whether it's at a stop light or a traffic jam.