GM 2.7L L3B Inline-4 Turbo Engine (Design, Problems & Reliability)
Updated: Feb 2
✔ This article has been fact checked.
The GM L3B is a 2.7 litre turbocharged four-cylinder engine, it's developed by General Motors for use in a variety of vehicles, with a focus on full-size pickup trucks and larger cars. The L3B engine made its debut with an SAE-certified output of 310 horsepower and 348 pound-feet of torque.
Since then, the engine has undergone several updates, including a high-output version that boasts even higher levels of torque, making it a powerful and efficient option for truck applications.
In this article, we will discuss the design and specs of the GM 2.7L L3B Inline-4 turbo engine as well as its reliability and tuning options.
Table of Contents:
L3B Engine Design
The GM L3B engine is a 2.7 litre turbocharged four-cylinder engine; it is a clean-sheet design developed by General Motors for use in various vehicles, focusing on full-size pickup trucks and cars.
This engine was specifically designed to meet the demands of truck applications and was first introduced in the 2019 Chevrolet Silverado 1500 and 2019 GMC Sierra 1500.
The L3B engine has a displacement of 2.7 litres and is configured in an inline-four cylinder configuration. The engine was developed from the outset as a truck engine to generate the strong low-end torque that customers expect in a truck.
The engine was designed to achieve a strong torque output with a long piston stroke of 4.01 inches (102mm); the piston stroke is the distance the piston travels up and down within the cylinder.
The long piston stroke enables improved combustion, resulting in a higher compression ratio and allowing the engine to produce more power while consuming less fuel.
The engine also features a unique offset crankshaft design, which allows for a more upright position for the connecting rods during their movement. This helps to alleviate the load of the pistons against the cylinder walls, reducing friction and improving efficiency.
The crankshaft and connecting rods are made of forged steel, a strong and durable material that can withstand high loads and stresses to support the high cylinder pressures that come with turbocharging.
The pistons are made of a tough aluminium alloy with a cast-iron ring groove insert, which allows for improved heat dissipation and increased durability.
The GM L3B engine also features an aluminium block and cylinder head for reduced mass, which helps to improve fuel efficiency and performance.
The GM 2.7L L3B engine is a powerful and efficient option for truck applications, specifically designed to meet the demands of truck applications, with advanced features such as the following.
A long piston stroke of 4.01 inches (102mm)
Offset crankshaft design
High-strength components (forged steel con-rods and crankshaft)
Reduced mass (aluminium block and head)
With the introduction of the 2022 Chevrolet Silverado, General Motors made significant changes to the L3B engine design to improve its performance and durability. These changes resulted in an increased torque rating of 420 lb-ft and also reduced noise, vibration, and harshness (NVH).
Engine Specs
Manufacturer | General Motors (GM) |
GM RPO Code | L3B |
Production | 2018+ |
Configuration | Inline four cylinder |
Displacement | 2.7 litres (2,727 cc) |
Cylinder Bore | 92.25 mm (3.63 in) |
Piston Stroke | 102 mm (4.02 in) |
Valvetrain | DOHC, 4 valves per cylinder with VVT (variable valve timing) and VVL (variable valve lift) |
Compression Ratio | 10.0:1 |
Firing Order | 1-3-4-2 |
Redline | 6100 RPM |
Black Material | 380 T5 Cast Aluminium |
Cylinder Head Material | 356 T5 Cast Aluminium |
Air Delivery | Single turbocharger, intercooled, 22-psi / 1.5 bar max boost |
Fuel Delivery | High-pressure direct injection (3000 psi / 20 MPa) and electronic throttle control, Active Fuel Management |
Ignition System | High-energy coil-on-plug |
Turbocharger | Single BorgWarner Dual-Volute with electrically-actuated wastegate |
Fuel Type | Gasoline (Petrol) |
Fuel Injection System | Gasoline Direct Injection |
Oil System | Wet Sump |
Cooling System | Water-Cooled |
Power Output | 237-325 hp (177-242 kW) |
Torque Output | 259-430 lb⋅ft (351-583 N⋅m) |
Additional Features
Some of the additional features included on the 2.7L L3B engine include the following.
Continuously variable oil pump
Electric water pump
Engine oil cooler
Automatic stop/start system
Active Thermal Management system
Exhaust manifold integrated within the cylinder head
Fuel Economy
The GM 2.7 Turbo engine, also known as the L3B engine, is known for its efficient performance in terms of fuel economy.
The engine is equipped with advanced technologies such as a high-pressure fuel injection system and a continuously variable valve timing system which helps to optimize combustion, resulting in improved fuel efficiency.
Additionally, the engine's lightweight aluminum construction helps to reduce weight and improve fuel economy by reducing the load on the engine.
The GM 2.7 L3B Turbo engine is an efficient engine in terms of fuel economy.
Problems & Reliability
Despite the GM 2.7 Turbo engine's efficient performance and advanced technologies, the engine has been reported to have some issues and reliability concerns.
It's worth noting that these issues are not necessarily widespread, and they are not necessarily indicative of a lack of reliability for the GM 2.7 Turbo L3B engine.
However, if you are considering buying a vehicle with this engine, it is important to do your own research and take these issues into account before making a decision.
Additionally, if you already own a vehicle with this engine and are experiencing any of these issues, it is recommended to take your vehicle to an authorized dealer for proper diagnosis and repair.
Some of the most common reported issues include the following.
1. Engine Carbon Build-Up
Some owners have reported that their engines have developed carbon build-up on the intake valves and ports, which can affect engine performance and fuel efficiency.
This can be caused by a variety of factors such as using low-quality fuel, infrequent oil changes, or not driving the vehicle frequently enough to allow the engine to fully warm up.
2. Fuel Injector Issues
Some owners have reported issues with the engine's fuel injectors, which can affect engine performance and fuel efficiency. This can be caused by a variety of factors such as a clogged fuel filter, a malfunctioning fuel pressure regulator, or a malfunctioning engine control module.
3. High-Pressure Fuel Pump Problems
Some owners have reported issues with the engine's high-pressure fuel pump, which can affect engine performance and fuel efficiency.
This can be caused by a variety of factors such as a clogged fuel filter, a malfunctioning fuel pressure regulator, or a malfunctioning engine control module.
4. Active Fuel Management System Issues
Some owners have reported issues with the engine's Active Fuel Management system, which can affect engine performance and fuel efficiency. This can be caused by a variety of factors such as a malfunctioning engine control module, a problem with the engine's sensors, or a problem with the engine's vacuum lines.
5. 4% Of L3B Engines Have Major Issues
Some owners have reported major issues with their L3B engines such as cylinder head issues and internal engine problems.
These issues can be caused by a variety of factors such as a manufacturing defect, a problem with the engine's components, or a problem with the engine's assembly.
Is It a Good Engine?
The GM 2.7 Turbo L3B is a powerful and efficient engine, with advanced technologies such as a high-pressure fuel injection system, continuously variable valve timing, and a lightweight aluminum construction that improves fuel efficiency and performance.
The engine's high-output version boasts even higher levels of torque, making it a powerful and efficient option for truck applications.
However, the engine also has some reported reliability issues such as engine carbon build-up, fuel injector issues, high-pressure fuel pump problems, and issues with the Active Fuel Management system.
Additionally, about 4% of L3B engines have been reported to have major issues such as cylinder head and internal engine problems. These issues may affect the engine's overall performance and longevity.
It's worth noting that these issues are not necessarily widespread, and they are not necessarily indicative of a lack of reliability for the GM 2.7 Turbo engine. However, they are important to consider when deciding whether to buy a vehicle with this engine.
It remains to be seen how these issues will impact the engine's overall performance in the long term.
The GM 2.7 L3B Turbo engine is a powerful and efficient option for truck applications, however, it does come with some reported reliability issues.
Therefore, it is important to do a thorough research and analysis before making a decision on whether to buy a vehicle with the L3B engine and to weigh the pros and cons of the engine based on your personal needs and preferences.
Is the L3B Engine Reliable?
The GM L3B engine, also known as the 2.7-liter turbocharged four-cylinder engine, is a relatively new design developed by General Motors for use in a variety of vehicles, with a focus on full-size pickup trucks and cars.
While the engine is known for its powerful and efficient performance, it has been reported to have some issues and reliability concerns.
It's worth noting that these issues are not extremely common and does not mean the engine is unreliable. However, these issues are important to consider when deciding whether to buy a vehicle with this engine.
When it comes to the question of whether the L3B engine is reliable or not, it is difficult to give a definitive answer without more long-term data on the engine's performance and reliability.
However, it is important to note that the engine has some reported issues and it is important to do a thorough research and analysis before making a decision on whether to buy a vehicle with the L3B engine.
It is also important to consider the warranty offered by the manufacturer and to keep up with regular maintenance to ensure the engine runs at its best.
Does It Require Premium (High-Octane) Fuel?
The question of whether the GM 2.7 Turbo, also known as the L3B engine, requires premium (high-octane) fuel or not is not entirely clear.
General Motors has not officially stated whether or not the L3B engine requires premium fuel, but it is likely that the engine is designed to run on regular gasoline with a minimum octane rating of 87.
It's important to note that using regular gasoline with an octane rating lower than 87 may cause engine knock and damage to the engine over time.
An octane rating is a measure of a fuel's ability to resist "knocking" or "pinging" during combustion, caused by the air/fuel mixture detonating prematurely in the engine.
However, using higher octane fuel may provide some benefits such as better performance and reduced engine knock.
It's also worth noting that, while the engine is designed to run on regular gasoline, using higher octane fuel may provide some benefits such as better performance and reduced engine knock.
In addition, using premium fuel may also help to protect the engine and prolong its lifespan by reducing the risk of engine knock and other forms of engine damage.
To be certain, it is best to consult the vehicle owner's manual or the manufacturer for recommendations on the type of fuel and octane rating to use.
Performance Upgrades & Tuning
The GM 2.7 Turbo engine is a powerful and efficient option for truck applications, however, there are several performance upgrades and tuning options available for those looking to improve its performance even further.
Some of the most popular performance upgrades and tuning options include the following.
ECU Remapping: This process involves reprogramming the engine control unit (ECU) to optimize the engine's performance. ECU remapping can be done by a professional tuner and can result in increased horsepower, torque, and improved throttle response.
Intake Upgrades: Upgrading the air intake system can improve the engine's performance by increasing the amount of air that the engine can intake. This can be done by installing a high-performance air filter, a cold air intake, or a ram air intake system.
Exhaust Upgrades: Upgrading the exhaust system can improve the engine's performance by reducing backpressure and increasing exhaust flow. This can be done by installing a high-performance exhaust system, headers, or a cat-back exhaust system.
It's important to note that performance upgrades can void the vehicle's warranty, so it's important to check with the manufacturer before making any modifications.
Additionally, it is always recommended to have a professional mechanic or tuner perform the upgrades and tuning to ensure that the vehicle is safe to use and drive.
Engine Vehicle Applications
Below are the vehicles the GM 2.7 L3B Engine is being used in.
Production Year(s) | Vehicle Model | Power Output | Torque Output |
2019-2021 | Chevrolet Silverado and GMC Sierra 1500 | 231 kW (310 hp) @ 5600 RPM | 348 lb⋅ft (472 N⋅m) @ 1500 RPM |
2022+ | Chevrolet Silverado and GMC Sierra 1500 | 231 kW (310 hp) @ 5600 RPM | 420 lb⋅ft (569 N⋅m) @ 1500 RPM |
2020+ | Cadillac CT4 | 231 kW (310 hp) @ 5500 RPM | 350 lb⋅ft (475 N⋅m) @ 1500 RPM |
2020+ | Cadillac CT4-V | 242 kW (325 hp) @ 5500 RPM | 380 lb⋅ft (515 N⋅m) @ 2000 RPM |
2023 | Chevrolet Colorado (detuned with different components, GM RPO code L2R) | 177 kW (237 hp) @ 5600 RPM | 259 lb⋅ft (351 N⋅m) @ 3000 RPM |
2023 | Chevrolet Colorado | 231 kW (310 hp) @ 5600 RPM | 390 lb⋅ft (529 N⋅m) @ 3000 RPM |
2023 | Chevrolet Colorado and GMC Canyon | 231 kW (310 hp) @ 5600 RPM | 430 lb⋅ft (583 N⋅m) @ 3000 RPM |
Sources
Wikipeda. "GM L3B Engine" https://en.wikipedia.org/wiki/GM_L3B_engine