The LLT engine was replaced by the GM LFX in 2012 with the release of the new model year. The 3.6-liter V6 engine in the LFX makes 301-323 horsepower and 262-278 pound-feet of torque.
The LLT, the LLT’s predecessor, was introduced to the public in 2006 in a variety of GM vehicles. New fuel injectors and intake valves, a new fuel pump and an updated intake manifold were included in the Chevy Camaro LS’s introduction of the LFX. The cylinder head also received an updated design with an integrated exhaust manifold.
The LFX engine is 20 pounds lighter and has 11 horsepower and 5 pound-feet more top-end torque than the LLT. The LFX is also E85 compatible, thanks to its higher compression ratio of 11.5:1..
The LFX had mostly been phased out by 2017, but it was still available in the Chevy Impala until 2020. The LGX, which was introduced in 2016 and is still in use, replaced the LFX. The LGX, which was also a direct-injected engine, had its bores and intake and exhaust valves increased slightly. A new cylinder head and higher RPMs were also added, resulting in increased power and torque of up to 335hp and 285lb-ft.
Cars that use the GM LFX Engine
Also in Australia, the LFX was used in several Holden models like the Caprice and Commodore.
- 2012-2016 LaCrosse
- 2013-2015 ATS
- 2012-2015 CTS
- 2012-2016 SRX
- 2013-2019 XTS
- 2012-2015 Camaro
- 2012-2017 Caprice
- 2015-2016 Colorado
- 2013-2017 Equinox
- 2012-2020 Impala
- 2015-2016 Canyon
- 2013-2017 Terrain
LFX Engine Problems
- Excessive Oil Consumption
- Water Pump Failure
- Front Cover Oil Leaks (Timing Chain Cover)
- Timing Chain Failure (mostly LLT engines)
1. Excessive Oil Consumption
Every 2,000 miles, the LFX engine can use up to a quart of oil. GM claims this is normal consumption, but the oil change intervals are to blame for the issues. An oil change is recommended after approximately 8,000-12,000 miles, according to software in the LFX.
The problem is that the engine runs out of oil at 1 quart every 2,000 miles before the check engine oil light comes on. Drivers are frequently surprised to discover that they are low on oil between oil changes, even though the low engine oil light may still illuminate.
The cam phasers are the first part of these engines to run out of oil when the oil level is low. Poor engine timing can cause cylinder misfires and codes to be thrown for the camshaft sensor if the phasers aren’t properly lubricated.
Moreover, the timing chain runs out of oil, and that’s when problems start to occur. Timing chain failure is frequently caused by excessive oil consumption, which depletes the oil supply.
LFX Oil Consumption Symptoms
- Low engine oil light
- Losing 1 quart of oil every 2,000 miles or more
- Camshaft sensor engine code
- Timing chain failure
How to Prevent or Fix Oil Consumption
Unfortunately, it’s normal for these engines to use a lot of oil. However, there is less of a problem with excessive oil consumption. There’s a problem when drivers don’t check their oil levels and keep going despite the low levels. If you follow General Motors’ recommended oil change intervals, you should top off the oil every 8,000 miles or so.
GM recalled this part for OLM (oil life monitoring) vehicles so that the system could be re-calibrated to suggest getting your oil changed sooner. We recommend having this done if you haven’t already in order to avoid having low oil levels.
The oil should be changed every 5,000 miles, but you can keep an extra quart or two in your trunk and top it off as needed.
The timing chain and cam phasers can be adequately lubricated with a GM oil supply kit, but it takes about 15 hours of labor to install it. If your warranty is still active, this might be an option. Otherwise, the extra cost of the oil supply kit isn’t worth it. Just make sure you don’t run out of oil.
2. LFX Water Pump Failure
Coolant is circulated throughout the engine via water pumps. This system is in charge of keeping the engine’s temperature within the acceptable range. High pressure is applied to the internal parts of a water pump. The water pump’s internal components, including the gasket and seals, wear out over time due to the internal pressure.
As the pump’s internal components degrade, it works harder to keep the coolant flowing. Leaks in the gasket or seal cause pressure drops in the system, which puts additional strain on the water pump.
The water pump on the LFX engine frequently fails between 80,000 and 100,000 miles. A failing water pump will have warning signs, so you can catch them before the engine overheats due to the pump failing completely.
The “weep” hole on the LFX water pump is a small drain hole. Coolant will drip from the weep hole when the water pump begins to leak internally, and this is a sure sign that the water pump will fail soon.
LFX Water Pump Failure Symptoms
- The engine’s cooling system has a leak.
- Overheating of the engine (water pump has already failed)
- Engine whirring noise
There is a good chance that you are overheating because your water pump has failed. Finding small coolant leaks around the engine indicates that the water pump is likely to fail, but it hasn’t done so fully.
If you notice coolant leaks, it’s time to replace the water pump. If left unchecked, overheating can ruin head gaskets, internals, and cause a slew of other issues. A water pump replacement on the LFX will likely cost you around $1,000 at a dealership. The parts, on the other hand, should cost no more than $100, and assembly will only take a few hours.
3. LFX Timing Chain Cover Leaks
Often referred to as the “front cover,” the timing chain cover serves to protect and lubricate the drivetrain components. To keep the timing chain from becoming entangled in road grime and debris, the cover bolts directly onto the front of the engine block. In reality, the timing chain cover’s primary function is to help keep engine oil lubricated.
Because the LFX does not use a timing belt but rather a timing chain, it has a metal front cover. A gasket separates the cover from the block before it is bolted on. Because it’s so close to the engine, the gasket gets a lot of heat. As a result of the wear and tear caused by the heat, the front cover gasket eventually fails and oil leaks out.
The gasket is also responsible for sealing the engine’s vacuum or pressure. The failure of a gasket can lead to a number of performance-related issues, such as oil leakage, engine pressure leakage, and more.
Symptoms of a Failing LFX Timing Cover Gasket
- The timing cover is dripping oil, and the timing block and cover are both oil-stained.
- Engine light on because of low oil or excessive oil use
- The engine has poor performance and runs poorly.
- The sound of an engine knocking can be heard.
- Vacuum leaks, AFR issues, and other problems can be indicated by an engine code.
- These are the P0016-P0019 codes: (usually associated with chain failure)
While a timing chain cover can be cracked, gasket failure is the most common cause of LFX problems. Gasket failure must be addressed immediately to avoid further engine damage and poor performance. It can also lead to low oil levels, which can further damage the timing chain and other internal components of the engine.
4. LLT & LFX Timing Chain Failure
Low oil levels are the most common cause of timing chain problems. In the same way that excessive oil consumption can lead to low oil levels, oil levels can also be caused by an oil change monitoring system that suggests too few oil changes.
The timing chain is one of the first parts to run out of oil when the engine’s oil level is low. Due to a lack of lubrication, the timing chains become overly frictional, which raises their operating temperature. As the temperature of the timing chain metal rises, the chains stretch and can jump gear teeth.
The problem is exacerbated even further by the timing chain tensioner. The tensioner’s job is to keep the chain taut so that it doesn’t jump gears when it’s not supposed to. In other words, the tensioner is hydraulically actuated and works by applying oil pressure. Due to insufficient oil pressure, the tensioner loses its ability to keep the chain taut, resulting in a malfunction.
If the timing chain guides aren’t kept lubricated, they will wear out and need to be replaced.
Is timing chain failure an LFX problem?
Between 2007 and 2011, the LLT engine had a high number of timing chain issues. SRX, Camaro and Impala models from 2012 were also impacted. The timing chains were upgraded in April of that year, reducing future problems to a minimum.
As a result, timing chains are considered to be high-maintenance and subject to failure. As early as 30,000 miles on affected 2007-2012 models, they are known to fail and should last closer to 150,000 miles on later models without these issues.
GM recalled and re-calibrated oil life monitoring systems on vehicles equipped with them to avoid the need for lengthy oil changes and reduce the risk of running out of oil.
LLT & LFX Timing Chain Failure Symptoms
- Various engine codes
- P0008, P0009, P0016, P0017, P0018, P0019
- Poor engine timing
- Engine runs poorly, idles poorly, etc.
- Cylinder misfires
- Metal shavings in oil
Failure of a timing chain can cause an engine’s timing to be completely out of sync. It’s critical not to start your engine if your timing chain breaks completely or jumps too many teeth. When the engine is run with poor timing, the valves can collide with the pistons, resulting in severe damage to the engine’s internal components.
LFX Engine Reliability
Due to the frequency of timing chain failure, the LLT engine received a bad reputation for dependability. For the most part, this problem was solved by upgrading the LFX engines or recalibrating the oil level monitors in vehicles equipped with OLM.
In comparison to 2013 and later LFX models, 2012 models suffered from timing chain problems. To be honest, though, this is only an issue if your oil levels get dangerously low. Our recommendation is to top off oil every 2,000 miles or so if your LFX is known to use 1 quart every 2,000 miles or so.
GM recommends oil changes every 8,000 to 12,000 miles, but if you don’t drive that many miles a year, we recommend changing the oil more frequently.
Aside from issues that can arise when the oil level is low, the LFX’s engine has proven to be dependable. The oil consumption issues with the LFX should be taken into consideration if you own or plan to own one. You should also check your oil levels frequently to ensure that they do not fall dangerously low.
The LFX engine should be able to reach 200k miles with proper oil level maintenance. Just keep in mind that by the time you reach these odometer readings, a number of maintenance items such as water pumps, hoses, timing chains, sensors, and so on will likely have developed.
Please share your thoughts on the LFX engine in the comments section below.