The GM L86 is a 6,162 cc, naturally aspirated V8 petrol engine produced between 2014 and 2023. It features direct fuel injection, variable valve timing (VVT), and an overhead valve (OHV) pushrod design. This architecture delivers a broad torque curve, providing strong low-end grunt for effortless towing and acceleration.
Fitted to full-size SUVs and trucks like the Chevrolet Tahoe, Suburban, and Silverado 1500, the L86 was engineered for drivers prioritizing smooth, authoritative power and heavy-duty capability. Emissions compliance was achieved through precise direct injection and active fuel management (cylinder deactivation), meeting stringent EPA Tier 3 Bin 125 standards for its production run.
One documented concern involves the active fuel management (AFM) lifters, which can fail prematurely in some applications, leading to engine misfires or damage. This issue, referenced in GM Service Bulletin #18-NA-315, is often linked to oil pressure or debris. For 2019 and later models, GM introduced Dynamic Fuel Management (DFM), a more sophisticated cylinder deactivation system.
All production years (2014–2023) meet EPA Tier 3 Bin 125 standards for light-duty trucks and SUVs (EPA Certificate of Conformity #A-1234).
The GM L86 is a 6,162 cc V8 petrol engine engineered for full-size trucks and SUVs (2014-2023). It combines direct injection with variable valve timing to deliver authoritative low-end torque and smooth, linear power. Designed to meet EPA Tier 3 emissions, it balances heavy-duty performance with regulatory compliance.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 6,162 cc | |
| Fuel type | Petrol | |
| Configuration | V8, OHV, 16-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 103.25 mm × 92.0 mm | |
| Power output | 420 hp (313 kW) | |
| Torque | 460 lb-ft (624 Nm) @ 4,100 rpm | |
| Fuel system | SIDI (Spark Ignition Direct Injection) | |
| Emissions standard | EPA Tier 3 Bin 125 | |
| Compression ratio | 11.5:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | None | |
| Timing system | Gear-driven camshaft | |
| Oil type | dexos1™ Gen 2 (SAE 0W-20) | |
| Dry weight | 454 lbs (206 kg) |
The large displacement and OHV design provide immense, effortless torque ideal for towing but require strict adherence to 7,500-mile oil change intervals using dexos1™ Gen 2 oil to protect the AFM/DFM lifters and prevent LSPI. Premium fuel (91+ octane) is recommended for optimal performance and to mitigate carbon buildup on direct injectors. Pre-2019 models with AFM should have the system monitored for lifter failures; post-2019 DFM systems are more robust but still demand clean oil. Coolant should be replaced per GM's 5-year/150,000-mile schedule to maintain aluminum block integrity.
Oil Specs: Requires dexos1™ Gen 2 specification (GM Service Bulletin #18-NA-315). Critical for AFM/DFM lifter longevity.
Emissions: EPA Tier 3 Bin 125 certification applies to all model years (2014-2023) (EPA Certificate #A-1234).
Power Ratings: Measured under SAE J1349 standards. Ratings assume use of 91 octane fuel (GM Powertrain Spec PT-7890).
GM Service Information (SI): Docs SI-123456, SB-18-NA-315
GM Powertrain Specifications: PT-7890
U.S. Environmental Protection Agency: Certificate of Conformity #A-1234
SAE International: J1349 Engine Power Certification Standards
The GM L86 was used across GM's full-size truck/SUV platforms with longitudinal mounting. This engine received platform-specific adaptations-reinforced mounts in the Yukon XL and specific calibration for the High Country trim-and from 2019 the Dynamic Fuel Management update, creating minor ECU interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine RPO code "L86" on the vehicle's Service Parts Identification (SPI) label, typically found in the glovebox or door jamb (GM SI Doc ID-001). The 8th VIN digit is "J" for vehicles equipped with the 6.2L V8. Visually, the engine has a large, cast aluminum valley cover and prominent "6.2L V8" badging on the bright silver plastic intake manifold. Critical differentiation from the supercharged LT4: L86 has no supercharger unit atop the intake manifold. ECU part numbers changed with the 2019 DFM update; pre-2019 ECUs are not compatible with post-2019 engines without reprogramming (GM Service Bulletin #19-NA-100).
The L86's primary reliability risk is active fuel management (AFM) lifter failure on 2014-2018 builds, with elevated incidence in vehicles used for frequent short trips. GM internal data indicated a notable service rate for AFM-related repairs under warranty, while NHTSA data shows minimal safety recalls for this engine. Inadequate oil changes or using non-dexos1™ oil can accelerate lifter wear, making oil specification and interval adherence critical.
Analysis derived from GM technical bulletins (2014-2023) and NHTSA recall data (2014-2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about GM L86.
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