The GM L3Z is a 3,299 cc, turbocharged inline — three petrol engine produced from 2020 to present. It features direct fuel injection, a single twin — scroll turbocharger, and variable valve timing (VVT) to deliver a blend of efficiency and spirited performance. In its primary application, it produces 155 kW (207 hp) and 350 Nm of torque, offering strong low — end pull characteristic of modern turbocharged engines.
Fitted exclusively to the Chevrolet Trailblazer ACTIV and R…
Production years 2020–Present meet U.S. EPA Tier 3 Bin 30 and California LEV III SULEV30 standards (U.S. EPA Engine Family Certification: GGMTA.07L3ZLX).
The GM L3Z is a 3,299 cc inline-three turbocharged petrol engine engineered for subcompact SUVs (2020-Present). It combines direct injection with a twin-scroll turbocharger to deliver strong low-end torque and efficient performance. Designed to meet U.S. EPA Tier 3 and California LEV III SULEV30 standards, it balances urban agility with regulatory compliance.
| Parameter | Value | Source |
|---|---|---|
Displacement | 3,299 cc | |
Fuel type | Petrol (Gasoline) | |
Configuration | Inline-3, DOHC, 12-valve | |
Aspiration | Turbocharged | |
Bore × stroke | 86.0 mm × 94.6 mm | |
Power output | 155 kW (207 hp) @ 5,500 rpm | |
Torque | 350 Nm @ 1,500–4,000 rpm | |
Fuel system | Direct Injection (SIDI) | |
Emissions standard | U.S. EPA Tier 3 Bin 30, CA LEV III SULEV30 | |
Compression ratio | 10.0:1 | |
Cooling system | Water-cooled | |
Turbocharger | Single twin-scroll (Mitsubishi Heavy Industries) | |
Timing system | Chain-driven | |
Oil type | dexos1™ Gen 3 (SAE 0W-20) | |
Dry weight | Approx. 135 kg |
The GM L3Z was used exclusively in the Chevrolet Trailblazer platform with transverse mounting. This engine received no platform-specific adaptations outside of its primary application. All service information and parts are consistent across its production run. All adaptations are documented in OEM technical bulletins.
The L3Z's primary documented concern is potential turbocharger wastegate rattle or sticking, with elevated incidence in vehicles subjected to frequent short trips. GM service information PIP6123B outlines diagnostic and repair procedures, while owner feedback often cites minor oil consumption, though widespread failure is not officially documented. Extended idling and low-quality fuel can exacerbate turbo and GPF issues, making adherence to maintenance schedules critical.
Analysis derived from GM technical service bulletins (2020-2024) and aggregated owner-reported data (2021-2024). Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
The L3Z is generally considered reliable for its intended use in the Trailblazer. Its primary documented issue is the turbo wastegate, addressed in service bulletins. Long-term reliability is heavily dependent on using the correct dexos1™ Gen 3 oil, adhering to service intervals, and allowing the GPF to regenerate through regular highway driving.
The most frequently discussed issues are turbocharger wastegate rattle or sticking (covered in GM PIP6123B), potential GPF clogging from short trips, minor oil consumption within normal limits, and coolant leaks from thermostat housings or hoses. These are documented in GM service information.
The L3Z engine is used exclusively in the Chevrolet Trailblazer, specifically in the ACTIV and RS trim levels, from the 2020 model year onwards. It is not found in any other GM vehicles.
Yes, the L3Z responds to ECU tuning. Simple flashes can yield modest gains of 15-25 hp by optimizing boost and timing. Significant power increases are limited by the stock turbo and the need to protect the GPF. Hardware upgrades are complex and uncommon for this application.
Fuel economy is competitive for its class. EPA estimates for a FWD Trailblazer RS are around 29 mpg city / 31 mpg highway. Real-world figures vary with driving style, often ranging from 27-30 mpg combined for most owners.
Yes. The L3Z is an interference engine. If the timing chain fails (a very rare event), the pistons can collide with the open valves, resulting in significant internal engine damage requiring a major rebuild or replacement.
GM mandates dexos1™ Generation 3 full synthetic oil, typically in 0W-20 viscosity. Using the correct specification is crucial for protecting against low-speed pre-ignition (LSPI), ensuring turbo longevity, and supporting GPF function.
Comprehensive technical documentation and regulatory references
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EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
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DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
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UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
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