The 6.4L Hemi engine offers drivers power and performance that is hard to match. This engine has great fuel economy and makes driving a pleasure. If you are looking for an engine that will give you the power you need while also being fuel efficient, the 6.4L Hemi is the right choice. Reviewers say that this engine is reliable and built to last, making it a great option for anyone looking for an upgrade. Whether you are a first-time buyer or experienced driver, the Dodge 6.4L Hemi is sure to impress. Read on to learn more about this amazing engine!
Chrysler 6.4 L Hemi Engine Review [hide]
Chrysler HEMI 6.4 L Engine Specs
The HEMI engine has been a long standing name in the world of engines. Since being introduced, nearly fifty years ago, it has become known as a powerful and trustworthy engine. It was originally developed by the Chrysler Corporation to power their vehicles during World War II. Soon after its development, thanks to several issues that have since been resolved, it was decided that the HEMI engine would not be produced any longer. It has since been reintroduced to the world of engines and has become one of the go-to engines for many car manufacturers.
The 6.4 L Hemi is a gasoline-powered V8 engine used for powering trucks and sport utility vehicles (SUVs). According to FCA US LLC , it measures 15 inches wide by 18 inches high and 23 inches long, weighs over 400 pounds when dry, and is capable of putting out up to 465 foot-pounds of torque per minute when at peak power.
- Manufacturer: Chrysler
- Production years: 2008
- Engine displacement: 392 cubic inches, 6.4 liters
- Horsepower/Torque output: 450 hp @ 5,600 RPM / 490 lb-ft of torque @ 4,000 RPM
- Power-to-weight ratio: 9.48 hp/lb
- Transmission options: 6-speed manual [MCT] & 5 speed automatic [AHT]
Chrysler 6.4 L Engine Overview
Mopar’s 6.4 L Hemi V8 was announced in the Spring of 2008, just before being implemented into its core vehicle applications. The SRT-8 version of this engine followed shortly thereafter, appearing in the Charger and Challenger models at the beginning of 2009. During its first year on sale, it quickly became known for delivering neck-snapping acceleration with surprisingly good fuel economy – not to mention a spine tingling exhaust note.
When Chrysler originally released details about this engine back in ’08, they let slip that it would produce 475 hp @ 5250 rpm and an impressive 490 ft-lbs of torque @ 3800 rpm. However, those numbers didn’t remain unchanged over time as engineers kept making improvements to the engine. Eventually, Chrysler increased the power output to 510 hp @ 5200 rpm and 525 ft-lbs of torque @ 4000 rpm – all while giving it better durability at higher operating temperatures. The original horsepower rating also held only when the ignition timing was set below 24 degrees BTDC (Brake Mean Effective Pressure). When set at 35 degrees BTDC, Chrysler engineers discovered that this engine was capable of producing 530 hp.
As good as those numbers were though, they only applied to the SRT8 models fitted with a manual transmission. If you ordered your SRT8 with an automatic transmission instead, then you were relegated to 470 hp and 465 ft-lbs of torque for safety reasons. What few people realize is that even if your SRT8 came with an automatic, you could still order it with the 6.1 L Hemi engine – just not at the same horsepower level.
Chrysler 6.4 L Engine reliability
Chrysler 6.4 L engineers, designers, and technicians were well aware that their new Hemi engine would be put to the test in some of the most grueling conditions imaginable when they designed it. The 6.4L HEMI was introduced in 2008 with an impressive list of high-end components and critical technologies that many believed would lead to trouble free, long life service while producing outstanding power levels within a broad range of operating conditions. This article provides insight into how Chrysler 6.4L owners are managing their engines today after 2 million miles or more have been accumulated by owners around the world during ongoing operation under serious joint/civilian off road use conditions and daily driving.
Chrysler 6.4 L Engine Key Features
The Chrysler HEMI 6.4 engine was introduced in 2008 with the release of the Challenger SRT8 and soon after in the Charger SRT8 as well. In 2009 it made its way to the Ram heavy duty pickups and it can be found under the hood of most models from 2012 until 2014, when it gave way to a detuned version. Some of the key features are:
- The 6.4 L Hemi is an all-aluminum OHV pushrod engine with desmodromic cylinder heads and dual overhead cam valves. It can be found in two variations; the first variation has a displacement of 392 cubic inches while the second (and most common) version has 403 cubic inches under its hood. The extra displacement was achieved by increasing the bore size; this increased torque at low RPM while reducing peak horsepower slightly.
- The 6.4 L Hemi comes equipped with Multi-Displacement System technology, which enables it to switch between running on all or four cylinders depending on current demands placed on the engine (for example idling consumes less power than wide open throttle). These changes are imperceptible to the driver as the change from two to four cylinders is done seamlessly.
- In order to achieve maximum performance out of a 6.4 L Hemi, it is necessary to use 91+ octane fuel all the time. Using anything less than that will result in loss of power output and possible damage to internal engine components, including piston ringland blowout which may occur when using regular instead of premium gas.
- A 6.4 HEMI produces 450 horsepower at 5,600 RPM with 490 lb-ft of torque at 4 ,000 RPM. This high torque level makes it easy for the engine to accelerate even with only two driven wheels . The maximum torque comes on early around 2 ,500 RPM while horsepower does not really start until 3,200 RPM.
- Variable displacement system to reduce fuel consumption when power isn’t necessary. This increases gas mileage by 10%. Chrysler’s six-speed automatic transmission enhances this capability even further.
- Active cylinder management, or ACM – allows for eight different modes for better performance and efficiency Engine will still run with only three cylinders turned on if there’s a problem in any one of them Exhaust brake feature, also known as EBD to assist the driver when descending a hill High flow intake manifold High flow exhaust manifolds
This engine is a complete breakthrough in technology. It makes the car safer and more efficient by optimizing emissions, fuel consumption, and eliminating risks that may arise from high temperatures or low cylinder pressures. This disruptive technology will continue to improve as time goes on. The Chrysler 6.4 L Hemi Engine Review helps consumers understand what makes this engine so great!
Chrysler 6.4 L Engine Horsepower
The Chrysler 6.4 L Hemi engine came as an option on the 2011 model year 200 and 300 sedans as well as Town and Country minivans. The engine got its power from a 5.7 L Hemi which was modified to create a true high performance unit that could be utilized by many models in Chrysler’s lineup, not just large cars and vans. This engine’s horsepower is up to 450.
Chrysler 6.4 L Engine Oil Viscosity
The manufacturer recommends using full synthetic SAE 0W-40 meeting Chrysler MS-12633 requirements.
Chrysler 6.4 L Engine Oil Capacity
The 6.4 L V8 engine it has an oil capacity of 7 quarts with a filter and the torque for the drain plug is 20 ft/lbs.
Best Oil for HEMI 6.4 L Engine
The good news is that your oil matters more than ever because of this engine’s unprecedented performance and potential longevity. Hemi engines provide premium high performance but use premium oil as well. Required oil type is MOPAR SAE 0W-40 engine oil approved to Chrysler Standard or equivalent Pennzoil or Shell Helix is recommended for all operating temperatures.
Pennzoil Ultra Platinum Full Synthetic 0W-40 Motor Oil
Valvoline European Vehicle Full Synthetic SAE 0W-40 Motor Oil
Mobil 1 – Synthetic Motor Oil 0W-40
Castrol 03101 Edge 0W-40 A3/B4 Advanced Full Synthetic Motor Oil
Liqui Moly Synthoil Energy A40 0W-40 Synthetic Motor Oil
Car models using HEMI 6.4 L Engine
The 6.4 L Hemi can produce roughly 410 horsepower at 5,600 RPM with torque output rated at 420 lb.-ft. at 4,000 RPM. This engine is a six-cylinder double overhead camshaft design with a cast aluminum compacted graphite iron block and aluminium alloy heads. It uses a compression ratio of 9.6:1 for a flat torque curve and improved fuel economy over the previous 5.7 L V8 HEMI .
The 6.4 Hemi features Multi Displacement System (MDS) technology to switch between 8 and 16 cylinders when needed to improve fuel economy by better than 30% in city driving conditions.
So, here are some car models using this powerful engine:
- Dodge Charger SRT8, SRT 392, R/T Scat Pack
- Dodge Challenger SRT8, SRT 392, R/T Scat Pack
- Chrysler 300 SRT
- Jeep Grand Cherokee SRT
- Dodge Durango SRT
- Ram 2500
- Ram 3500
Chrysler HEMI 6.4 L Engine life expancy
Hemi powered cars are known for their durability and longevity. With an average of around 250,000 miles or even more, so you can expect your 6.4 V8 Hemi engine to last through any adventure!
Common Problems with HEMI 6.4 L Engine
The Chrysler 6.4 L Hemi Engine is a high performance engine that has recently been employed in many full sized trucks and SUVs. A few years after it was first used, however, the engine began experiencing some problems including an issue known as “piston slap.”
A click-click-creak noise may be heard from the top of the engine when at idle speed with the hood open. The noise seems to come from between cylinder number one and number two on either side of the engine block. This noise does not indicate any real problem. It is actually an indication of excess clearance between the piston rings and cylinders. This space provides room for thermal expansion which can cause this type of or creaking sound sometimes called piston slap.
Take care not to confuse this noise with the sound of an oil leak; creaking noises tend to be less harsh and hollow sounding than oil leaks.
Another common problem is coolant leaking into the motor oil in the engine compartment. This may cause a loss of lubrication which can lead to bearing failure, cylinder damage, or complete engine breakdown. Damaged bearings will allow metal flakes to circulate throughout the engine in addition to the presence of potentially large quantities of abrasive particles within motor oil (which reduces its effective viscosity). These problems often require engine replacement. The cause of these types of failures are typically worn piston rings, warped cylinders, loose valve nuts, or stripped head studs.
Details on how to address these problems, including which problems are serious enough to require immediate attention, can be found below.
The best way to avoid these common problems is through preventative maintenance. Do not wait until your vehicle begins making strange noises because customers often try to fix the problem without addressing the cause of the noise or because they simply ignore it hoping that it will go away on its own.
Chrysler HEMI 6.4 L Engine Location
The location of the Hemi 6.4L varies from vehicle to vehicle because it can be used in three different types of vehicles, cars, SUVs ,and trucks. In each of these types, it is mounted differently. The engine is located in the truck with the front pointing towards the front of the vehicle, and then it points either straight up or slightly to the left.
In an SUV , the forward facing direction is pointed more to a side instead of towards a certain area. Finally, a car has a different location for this engine because it faces more towards the back rather than the front.
Replacing Chrysler HEMI 6.4 L Engine
If you’re wondering whether or not your Chrysler HEMI engine is bad, there are several signs to look out for. First of all, hydraulic lifters usually start to rattle when an engine has a problem. However, this issue typically occurs after 60k miles so don’t immediately expect that your car needs a new motor just because you hear some clicking noise from time to time –although it’s best to have a mechanic check things out anyway. The same thing applies to the “knocking” sound – if your car emits a rattling noise once in a while but it doesn’t happen often and the engine otherwise runs smoothly, there’s no point in trying to replace it right away. However, if you hear a loud knocking noise every time your motor is turned on and the sound doesn’t disappear even when you’ve driven a few miles or more, that means that something definitely needs to be fixed ASAP.
The engine replacement of an old Chrysler 300 shows how to easily replace a HEMI 6.4 L Engine yourself. The guide is for those who knows the basics about cars and want to save some money – no special skills or equipment required! More than that we’ll learn what we should pay attention on when buying used car, because Hemi engines are prone to problems after 100k miles.
First we should remove all unnecessary stuff: air filter box and intercooler tubes.
Then we take out the battery and disconnect cables from starter and transmission.
After that we take off under car shield plate to access bottom bolts of belly pan.
There are 5 bolts, 2 on each side of front axle, one behind it near frame rail. After removing these bolts we can easily loose belly pan over driveshaft and muffler… so keep in mind not to damage anything around when this heavy thing comes off – place something soft underneath before loosening bolts to prevent damage.
Then we have access to factory air intake system – 4 bolts on two flanges on each side of the engine bay.
After removing all these bolts and screws, some hoses are still connected with their clips, just carefully slide them out. Be sure that there are no electrical connectors or other stuff still connected before moving on! At this point some components should be loose already, but some more things need to be disconnected – first at exhaust manifold top cover where 2 bolts hold MAP (manifold absolute pressure) sensor harness:
MAP is used for fuel injection computer to make corrections for altitude etc., so it is important thing not to mix up or break anything here. After disconnecting MAP sensor connector we can easily take out the whole intake manifold, nothing holds it in place – just be careful with throttle cable connected to one of runners.
After this we can easily access injector wiring harness which is connected by 3 bolts.
Small piece on top of block under manifold may come off as well when you remove all bolts from front cover:
Now we have easy access to oil dipstick tube which is held with 1 bolt and will need to be pulled down a bit – most likely some oil will spill over, so prepare for it if your engine is still warm from driving before starting any work! After oil has drained completely from tube we can pull it out together with dipstick.
In next step we have to loosen 4 bolts around crankshaft to remove harmonic balancer pulley, then 2 bolts on each side of timing chain cover. If you are not sure how to do that safely – go take a professional with you or don’t attempt this yourself!
After removing timing chain cover we can access valve covers which are held with 8 nuts each, after removing them there’s no need to pull off valve covers completely yet.
Now it is time for intake manifold removal – throttle body has 3 bolts holding it to the head and all other stuff is connected by 2-3 hoses, 4 clamps hold everything in place. After disconnecting everything carefully slide out whole system over cylinder head and put somewhere safe where nothing can damage it while we work on engine.
Removing the old piston rings is the most important thing now – if you skip this step, you are not doing it right.
Clean each cylinder to remove all dirt and carbon deposits using Mopar Engine Cleaner additive (use hot water for better effect) or WD-40 penetrating fluid, clean up everything around as well.
Some of the pistons may be pretty dirty and it is good idea to soak them with gasoline or something else containing high percentage of fuel before starting any cleaning. After we have all cylinders cleaned we can start removing old rings by prying them carefully with screwdriver under ring gap.
It is advised to put some thick grease below new rings before trying to install them just to make sure that they stay in place during following steps!
After taking out old rings, clean cylinder walls thoroughly with lint-free cloth soaked in engine cleaner and blow dry them well.
Put thick grease around each ring and install them into cylinders carefully and slowly, be sure that they all go in their place without any gaps.
Now it is time for reinstalling intake manifold – before installing new gaskets be sure to use some gasket sealer below both sides of every connection just to prevent leaks.
New valve covers can now be installed – 2 bolts at front and 4 on each side hold it place.
Next step is to install water outlet and oil sensor – do not forget about their seals.
Now we can reinstall harmonic balancer pulley and tighten all bolts to recommended torque (10 foot pounds + 90°) except crankshaft bolt (25 foot pounds), then timing chain cover followed by intake manifold, throttle body etc. Now that whole part of the job is done, we can focus on valve train.
Before installing new timing belt we have to remove this metal guard which is holding it in place.
To take tension off camshafts and prevent them from rotating while you turn crankshaft clockwise, loosen both camshaft sprocket bolts and install 3mm allen wrench in one of them while having another one hold by vise grip pliers, then turn crankshaft bolt until that 3mm allen wrench is on top dead center (TDC) mark.
After TDC mark aligns with notch on the crank position sensor, tighten bolts holding camshaft sprockets and install new timing belt. On 1996-2000 engines it’s recommend to replace tensioner too… but beware – don’t over-tighten its bolt or you will most likely break plastic guide!
On 2000+ models Chrysler decided to install hydraulic tensioner which needs no attention except changing oil every 100000 miles or so – if yours is a 2000+ model, you can skip the tensioner part of this story.
Now it is time for cylinder head reinstallation – just reverse the whole process we have done before and you’re all set to go! In order to be able to start engine after installation, remove crank position sensor’s plastic cover on front of the engine and put 3 wires of new Crankshaft Position Sensor back where they belong.
In case you have any doubts whether your engine was built right or not (for example, if you don’t trust local machine shop too much) there’s no better way than installing and running it on your car with everything you’ve changed still in place, then scanning it with OBD II scanner for any codes. If everything is fine, no check engine light should show up – if one does, see Troubleshooting chapter of this article for details on what might be wrong.
If you want to make your 6.4l Hemi run better than stock there are couple things to keep in mind:
- Keep air filter well oiled (with motor oil) especially when cold outside to avoid loss of power due to too much airflow through the filter when cold etc.
- Make absolutely sure that your fuel pressure regulator doesn’t start leaking – if it starts dripping, fix it immediately before you destroy your engine! Check out FSM or Haynes manual for how it should look like when properly installed.
- Finally, keep an eye on your oil – do not run below minimum mark or you risk seizing pistons.