When you think of engine manufacturers, General Motors comes to mind as one of the best car manufacturers in the industry. GM has a Solid Gold Reputation in the automotive industry as they have designed and built some of the best cars on the road.
All their engine configurations — including inline-four, V6, and V8 are known for giving a thrilling adventure when hitting the road. One of their iconic V6 engines is the 3.6L engine. It has won several accolades and is considered reliable enough to be compared with their V8 engines. Though as reliable as it is, it has a fair share of pitfalls. You will learn the GM 3.6 V6 problems, history, versions, and reliability.
GM 3.6 v6 Engine Explained
The thrilling GM 3.6L V6 powerhouse made its first public appearance in a 2004 Cadillac CTS. Since then, it has evolved in different versions for better reliability and overall performance.
All the engine variations are designed and built in a 60-degree V6 configuration. It has a modern DOHC valvetrain layout — meaning it has four valves per cylinder. Two intake valves and two exhaust valves, making it 24 valves.
The 3.6L V6 GM engine features a multi-port fuel injection and variable cam phasing. Inside the engine lies an impressive forged crankshaft and connecting rods carefully engineered with precision for optimum performance. It has a variable-length intake manifold and a coil-on plug ignition system.
GM 3.6 V6 Versions
As I pointed out earlier, the 3.6L V6 GM engine has different versions and has appeared in different cars. Each of the versions has a unique code to differentiate it from the other.
LY7 is the first version of the GM 3.6L V6 engine. It made its first public appearance in a 2004 Cadillac CTS. Due to its reliability, other car manufacturers such as Suzuki, GMC, Holden, Saturn, Pontiac, Buick, and Chevrolet adopted the engine.
Suzuki changed the code name from LY7 to N36A. Engine torque and horsepower vary depending on the vehicle it was used. However, the torque ranges between 225 and 252 pounds-feet and horsepower between 211 and 275.
The LLT version arrived shortly after the first version — LY7. In this version, the GM engineers added a direct fuel injection system, which increased the fuel efficiency and engine power. The few adjustments made to this version also increased the compression ratio.
The LLT version appeared in the market in 2008 and continued until 2016. Like the first version, the LLT was used on different applications. One of these applications is the Chevy Camaro.
The next version in line of the GM 3.6L V6 engine is the LFX. The redesign on this version made the engine lightweight. GM also revised the intake valves, injectors, and a few other system components. However, the upgrade does not add much torque and power compared to the previous versions.
LFR & LFY
The LFR and LFY came shortly after the LFX with minor changes. In LFR, the engineers replaced the direct fuel injection system with a multiport fuel injection system, making the engine capable of running on CNG and gasoline. The LFY comes with a start-stop feature, which improves the airflow compared to the LFX version.
The LWR version was introduced in 2012, and the production continued until 2015. This version was seen mostly on many Holden models. It was specifically designed for the Austrian market. The multiport injection system used in this version made it capable of running on gasoline and LPG. It also features a vapor injection system, improving fuel economy and emission standards.
Like its predecessor, the LSC is designed and built for a unique purpose. This 3.6L V6 version is configured to run on a hybrid vehicle with lower engine power and torque. This engine was designed with a specific vehicle in mind. Unfortunately, the vehicle (2009 Saturn Vue Hybrid) the engine was designed for did not reach the production stage before it was canceled.
All the previous versions experienced minor changes. The LF3 version undergoes one of the most extensive upgrades since the 3.6L V6 GM engine debuted in 2004. GM engineers introduced forced induction, larger intake valves, stronger internals, and more to support the twin-turbo in the engine. Interestingly enough, the LF3 produced the highest torque and power compared to the previous versions. The engine outputs a claimed 430 pounds-feet of torque and 420 horsepower.
When General Motors planned to produce the Cadillac ATS-V, they needed something crazy much more than the LF3 engine. So, they decided to do some upgrades on the 3.6 V6 engine to increase the overall engine performance.
This quest brought about the LF4 engine. The upgrade includes revision on the twin-turbo, titanium connecting rods, improved engine boost, and more to enhance the engine torque and horsepower. At the end of the production, the engine could output 445 pounds-feet of torque and 464 horsepower in the Cadillac ATS-V.
LGX & LGZ
LGX and LGZ are the newer generation of the GM 3.6L V6 engine. The upgrade on these engine versions includes different bore sizes, architectures, updated variable valve timing, and more. They also have a feature that supports cylinder deactivation.
However, these newer generation engines do not use forced induction. This invariably makes its power and torque outputs comparable to the early versions.
GM 3.6 v6 Engine specifications
|Engine block material||Cast aluminum|
|Cylinder head material||Cast aluminium|
|Intake manifold material||Aluminium|
|Main bearing caps||Sintered steel|
|Exhaust manifold material||High-silicon Moly Cast iron|
|Camshaft material||Cast nodular iron|
|Connecting rod||Sinter forged steel|
|Crankshaft material||Forged steel|
|Numbers of cylinders||6|
|Valves per cylinder||4|
|Compression ratio||11.3:1 on LLT version
11.5:1 on LFY, LFR, LGX, and LFX
10.2:1 on LF3
|Fuel system||Direct injection
|Torque output||264-278 lb.ft on LFX
266-270 lb.ft on LLT
369-430 lb.ft on LF3
520 lb.ft on LF4
275 lb.ft on LGZ
|Power output||288 hp on LLT
301-323 hp on LFX
410-420 hp on LF3
464 and up to 600 hp on LF4
308 hp on LGZ
|Assembly sites||St. Catharines, Ontario
Ramos Arizpe, Mexico
Flint Engine South, Flint Michigan, USA
Romulus Powertrain, Michigan, USA
|Valve lifters||Roller follower with the hydraulic lash adjuster|
|Emission controls||Dual catalytic converters
Positive Crankcase Ventilation
|Applications||Buick Enclave, Chevrolet Traverse, GMC Acadia, Chevrolet Camaro, Chevrolet caprice, Chevy Impala, Chevy Equinox, Cadillac CTS, Cadillac SRX, Cadillac XTS, Cadillac ATS, Buick Lacrosse, GMC Terrain, Chevy Blazer, Chevy Colorado, GMC Canyon, Buick Regal GS.|
What GM models use the 3.6 v6 engine?
Before discussing the GM 3.6 V6 engine problems, let’s see the vehicles that use this engine. This list includes GM and vehicles from other manufacturers that use this engine.
- GMC Terrain
- Chevy Impala police vehicle
- Chevy Impala
- Chevy Caprice PPV
- Chevy Equinox
- Chevy Colorado 2015 to 2017
- Buick Regal GS 2018 to present
- Buick LaCroose
- Buick Rendezvous
- Chevy Camaro (Convertible and Coupe)
- Cadillac STX professional vehicle
- Cadillac SRX
- Cadillac CTS (Wagon, Sedan, and Coupe)
- Cadillac ATS sedan
- Cadillac STS
- GMC Acadia (AWD and FW)
- GMC Blazer 2019 to present
- GMC Canyon 2017
- Chevy Traverse (AWD and FWD)
- 2009 Buick Enclave (AWD and FWD)
- Saturn Outlook
- Saturn Vue-2 mode Hybrid.
What are the common problems with the GM 3.6 v6 engine?
The most common GM 3.6 v6 problems you don’t want to experience is timing chain issues. Early versions, such as the LF7, LLT, and LFX timing chains, are prone to stretching. Other GM 3.6 v6 common problems are water pump failure, excessive oil consumption, Camshaft actuator issues, and ignition coil issues.
Timing chain problems
The most common GM 3.6 V6 engine problem is timing chain issues. Early versions of the engine timing chains were prone to stretching. The timing chain is responsible for making sure the intake and exhaust valves open and close when they are supposed to.
A stretched timing chain will affect when the valves open or close and how long they stay open or close. This will affect the optimal engine performance. A GM 3 6 v6 timing chain problem will cause engine misfires, backfiring, poor idle quality, and a noticeable loss of engine power at specific RPMs.
However, the timing chain problems were fixed by the 2012 versions. So, if you are asking, did GM fix the 3.6 problems on timing chains? Now you know.
Water pump failure
Another 2004 to 2018 GM 3.6 v6 problem is water pump failure. While several 3.6 V6 GM engine owners have recorded several water pump failures, it’s not something you ever want to encounter.
The water pump plays a crucial role in the cooling system as it circulates coolants in the engine. If the water pump fails, the engine temperature will rise and cause overheat. If you just acquired a ride with the 3.6 V6 engine, it’s not time to panic yet. Most owners complain of water pump issues after covering 80k miles. But once you are approaching the 80k mile, be ready to change the water pump.
Camshaft actuator issues
Another prevalent problem is camshaft actuator issues. This problem is more common in early versions, and it occurs due to dirty or low engine oil. The camshaft actuators need adequate oil pressure to function properly. Hence, you must ensure you have enough oil at all times and do regular oil changes.
Requires frequent oil changes
While this engine is reliable and is not considered an engine that consumes much oil, some owners have complained otherwise. Some says they experience engine parts stalling, seizing, and grinding. This is one of the common GM 3.6 v6 problems in Colorado. It occurs in older and newer versions of the engine.
But keep in mind that the stalling, seizing, and grinding issues will not occur if you change the engine oil frequently. I recommend you carry an extra one or two quarts of oil in your trunk. Your oil may run down when you least expect it.
Ignition coil issues
Another GM 3.6 V6 engine problem, though not common is ignition coil issues. While the lifespan of the ignition coils on the 3.6 V6 engine largely depends on the car mileage and your driving style, it requires replacement more often than the ones on other GM engines.
When replacing the ignition coils, always purchase from a reputable brand and change the set of six at once. This will boost the engine performance and extend the lifespan of the ignition coils.
Did GM fix the 3.6 problems?
Yes, GM made several changes to address the 3.6 V6 timing chain problems by the 2012 version. However, engines after the 2012 model may still have timing chain problems, but it is much less than previous versions.
According to a thread on the GM insider news, General Motors fixed the timing chain issues by installing a better quality chain, dialing back the oil change interval, and improving the sprocket materials. So, if you are searching for GM 3.6 v6 problems forum discussion, click the link above.
How long does the GM 3.6 engine last?
The GM 3.6 V6 engine has been in production since 2004, when it first appeared in a 2004 Buick Rendezvous and Caddilac CTS. It is a reliable engine that can consistently reach more than 200,000 miles without major engine breakdowns but routine maintenance is a must.
While it has experienced its fair share of engine problems, the best way to extend the engine’s lifespan and keep your car running smoothly is by regularly performing oil changes.
Is the GM 3.6 V6 reliable?
Despite its fair share of problems, the GM 3.6 V6 engine is bulletproof, at least in the sense that it is reliable and powerful like most strong V8 engines. This power plant has various models with different specifications to meet your specific demand. Some are built for the Austrian market, some for hybrid applications, and some versions are built to output insane engine power and torque.