6.4 HEMI 392 Common Engine Problems
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The 4 Most Common 6.4 HEMI Engine Problems

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The Chrysler 6.4 HEMI debuted in 2005 with 525 horsepower and 510 torque. This variant is the crate engine under the name 392 HEMI. It wasn’t until 2011 that Chrysler actually began selling cars with the 6.4L Hemi engine. It’s a strong, reliable engine, but no engine is flawless and there aren’t any exceptions here. In this guide, I discuss a few of the common 6.4 Hemi engine problems along with overall thoughts on reliability.

6.4 HEMI 392 Common Engine Problems

392 HEMI Background Info

A few common names for the 6.4 HEMI include 392 HEMI and 392 Apache. The 392 represents the engine size in cubic inches while Apache is the codename for the 6.4L Hemi engine. One important note – the 392 HEMI crate engine shares few parts with the actual 6.4 Hemi available in factory cars. It’s a little odd since they both share the same names and displacement. However, the crate engine is a bit stronger and more performance-oriented.

That’s not to say the factory 6.4 is any slouch, though. In 2011, SRT8 models first receive the 6.4L HEMI with 470 horsepower and 470 torque. In 2015, output was increased to 485 horsepower and 475 torque. Ram 2500 and 3500 models receive a lower output variant of the engine. This was due to a need for better fuel economy and a better powerband for towing.

The engine is also very capable with tuning and basic performance upgrades. The 6.4 HEMI is capable of making 500+whp with these simple mods. We also have tons of other awesome, helpful content. If you’re interested in learning more, check out our ultimate 6.4 HEMI engine guide.

4 Most Common 6.4 HEMI Problems

A few of the most common problems on the Chrysler, Dodge, and Ram 392 engine include:

  • Multi-Displacement System (MDS)
  • Engine Tick
  • Transmission Failure
  • Misfires

We’ll circle back to this point towards the end of the post, but we want to clarify this now. The 392 HEMI is a reliable engine. We’re classifying the problems as a few of the most common. That’s not to say any of these problems affect a large percentage of engines. Also, other failures can and do happen from time to time so this is by no means an exhaustive list.

That said, let’s dive in and discuss each of the above problems one by one. At the end of the post, we’ll bring things full circle and wrap it up with some thoughts on Chrysler 6.4L reliability.

If you would rather consume this content via a video, check out our 6.4 HEMI Common Problems video below:

1) Multi-Displacement System Faults

Multi-displacement system (MDS) is a promising technology. While cruising the 6.4 HEMI is able to shut down 4 of the 8 cylinders. It’s a great way to use a larger engine to pump out more power while remaining efficient during lower-power situations. However, it’s still a relatively new technology. The main issue with the 392 HEMI MDS seems to be solenoid failures. Some also claim the 6.4 V8 MDS can feel a little clunky at times. Fortunately, the system can be manually shut off so all 8 cylinders are always firing.

There are a few long-term concerns about multi-displacement systems in general. For one, the 392 Apache MDS always shuts down the same 4 cylinders. Why could this be an issue? Well, there’s a lot of heat generated by the combustion process. Some of that heat is good. If the 6.4 HEMI shuts down 4 cylinders for an extended period those cylinders could run cooler. All reciprocating parts are still moving when the cylinders shut down. Allowing them to run cooler may cause longer-term issues with poor lubrication.

There’s some more that goes into that, but we’ll avoid writing hundreds more words and getting too technical. Point is – MDS is a promising technology, but has a few small kinks like solenoid failures. It’s also too new to say how the 6.4 HEMI MDS may impact reliability and engine longevity.

HEMI MDS Issues Are Speculation

The MDS solenoid failures can and do occur on the 392 HEMI engine. However, the long-term effects of multi-displacement systems are still speculated. Shutting down the same 4 cylinders for an extended period can have a negative impact. Spark plugs may foul quickly when they run too cold and are suddenly called back to use. Oiling is a potential concern on colder cylinders. Cylinders on the 6.4 HEMI may wear down unevenly over time. The list goes on and on. It’s purely speculation, but there are basic engineering concepts that suggest MDS could have negative impacts on longevity.

Don’t miss our HEMI MDS guide if you’re looking for more info and potential problems with the multi-displacement system.

2) Engine Tick Problems

Engine ticking on the 392 HEMI may tie into a few of the other common problems in this article. Specifically, the above MDS discussion. Ticking on the FCA 6.4 HEMI engine is an interesting issue. There are some claims that state that ticking is normal and will not affect longevity, reliability, or performance. However, some engine ticks have also led to complete engine replacement of the 6.4L HEMI. A few common causes of 6.4 HEMI engine tick include:

  • Faulty lifters
  • Seized lifter rollers

A few other minor things may lead to ticking on the Dodge 392 HEMI V8. However, our primary focus is on the above two bullets. This is also a common issue on the 5.7 HEMI. Lifter or lifter roller problems may be partially attributed to the multi-displacement system. It may not be the only cause, but it does make some sense. Lifter problems on the 6.4 HEMI likely boil down to poor oil flow over the lifter rollers which causes them to seize. Once this occurs, the lifter contacts the cam lobes and produces an audible engine ticking noise.

Of course, metal-on-metal contact also results in shavings of metal entering the engine oil. Usually, the oil filter will catch most of this metal if the 392 HEMI lifter problems are caught quickly. If left too long it’s possible for further engine damage to occur.

Faulty Lifter Roller Symptoms

Look for the following symptoms that may indicate a fault with the lifter rollers:

  • Ticking
  • Misfires
  • Check engine light

Problems with the 6.4 HEMI lifters can be tough to diagnose. It’s often simply the ticking sound without any other symptoms. This makes it especially challenging since others seem to notice 392 Apache ticking without any actual problems. In some cases, you may notice misfires or receive a check engine light – usually as the problem becomes severe.

The unlucky few who run into lifter roller failures typically notice issues around 80,000 to 120,000 miles. The below video is mostly in reference to the 5.7 HEMI, but it’s a good resource for more information on FCA 6.4 ticking and lifter rollers.

Lifter Roller Replacement

If caught quickly it’s unlikely additional engine damage will occur. However, at the least the engine will need to be opened up to replace the camshaft. Parts and labor on 6.4 HEMI cam replacement can quickly add up to $2,000+. Tack on some extra in the case metal shavings take out other parts like the oil pump. It’s possible for parts and labor to exceed the cost of a new remanufactured engine. As such, some replace the entire 392 HEMI engine.

3) 392 HEMI Transmission Failures

We’ll speed things up a bit moving through transmission and misfire problems on the 6.4 HEMI. Some of the 392 HEMI engines are mated to different transmissions. This of course depends on whether you’re talking about Dodge Charger’s or Ram 3500’s, for example. Problems appear to mostly occur on Ram 2500 or Ram 3500 trucks. It also may not be fair to consider these transmission failures among the most common issues.

It’s reasonable to assume many Ram 2500 and 3500 trucks are subjected to tough conditions towing heavy loads. This can put a lot of stress on a transmission and lead to premature wear and failure. Nonetheless, transmission problems can and do occur on Dodge, Chrysler, and Jeep models from time to time.

Again, it’s a very small percentage of failures. It is, however, worth the mention since it can be a costly issue.

Transmission Failure Symptoms

A few symptoms of transmission failure include:

  • Clunking sounds
  • Missing gears
  • Rough shifts

There are a few other possible symptoms, too. However, the transmission slipping, clunking, missing gears, or shifting too rough may indicate potential problems. Depending on the extent of the issues, you may need a new transmission for the FCA 6.4L Hemi V8.

Transmission Replacement

A transmission rebuild may be possible or a new trans may be needed. Either way, replacing the 6.4 transmission can add up to thousands of dollars. It’s not a problem we would put too much concern into. Transmission failures only affect a very small percent of vehicles.

4) Engine Misfires

Misfires can potentially be due to lifter roller or MDS solenoid issues. It’s also not totally fair to consider 392 HEMI misfires to be an actual problem. Misfires are often due to normal wear and tear items like spark plugs and ignition coils. That or misfires are simply a symptom of another underlying problem. Anyways, we’re really focusing on spark plugs here.

6.4 HEMI engines use 16 spark plugs. Yes, that’s correct – the 392 HEMI uses 2 spark plugs per cylinder. Then there are the standard 8 ignition coils. It’s a lot of ignition parts that may cause engine misfires. Spark plugs are wear-and-tear parts that usually require replacement every 60,000 to 80,000 miles. Ignition coils typically last about twice as long.

Premature failures aren’t too common on the 6.4 HEMI. However, it can happen especially with 16 spark plugs. Nonetheless, these are usually basic maintenance items. Don’t overlook spark plugs and ignition coils.

Misfire Symptoms

Symptoms of misfires on the Dodge, Ram, Chrysler, Jeep 6.4 HEMI include:

  • Fault codes
  • Stuttering
  • Rough idle
  • Poor performance

A misfire will likely trigger a fault code. You might also notice the 392 HEMI is stuttering, idling rough, or down on power. Most won’t notice the power loss since the engine will still be functioning properly on the other 7 cylinders.

Spark Plugs & Ignition Coil Replacement

Again, spark plugs are normal wear and tear parts on the 392 HEMI. Replacement is normal every 60,000 to 80,000 miles. Those who push their 6.4 HEMI’s hard may require earlier repairs. A set of 16 spark plugs come in around $100-150. It’s also a pretty simple DIY that most can knock out easily in the driveway. Ignition coils are a bit pricier, but typically last about 2x as long as the 6.4 spark plugs.

Chrysler, Dodge, Jeep, Ram 6.4 HEMI Reliability

How reliable is the 392 HEMI? Overall, the FCA 6.4 HEMI is a solid, reliable engine. It’s certainly not the most reliable engine in the world, but it’s also far ahead of the worst. We’ll give the 392 HEMI above-average remarks for reliability. It’s powered many flagship Dodge, Jeep, Chrysler, and Ram vehicles for nearly a decade. The 392 HEMI is also a fun, powerful workhorse that’s withstood the test of time. While a few of the common problems discussed can be pretty costly, they affect a pretty small number of engines.

That said, a lot of 6.4 HEMI reliability and longevity comes down to maintenance. It’s one of the things we can control. Ensure you’re using quality oils and changing it on time. If and when problems do pop up then repair them as soon as possible. With proper maintenance, chances are most 392 HEMI engines will hold up well beyond 200,000 miles.

6.4 HEMI Common Problems Summary

The 6.4 HEMI first began its life as a crate engine under the name 392 HEMI. In 2011, FCA began using the 392 Apache in production models beginning with the Dodge Challenger SRT8. Since then the engine found its way into many flagship performance models and trucks. It’s a stout engine that provides respectable performance and reliability. However, no engine is perfect.

A few of the most common problems on the 6.4 HEMI include MDS solenoids, lifter rollers, transmissions, and engine misfires. Some of the issues are potential effects of the 392 HEMI MDS system. That can, however, be manually disabled. While a few of the 392 HEMI problems can be expensive they only affect a pretty small number of engines.

All in all, the FCA 6.4 HEMI is a great engine. Maintain it well and fix issues in a timely manner when they do pop up. With proper maintenance, expect the 392 HEMI to last north of 200,000 miles.

What’s your experience with the 6.4 HEMI V8 engine? Are you considering one?

Drop a comment and let us know!

Also, check out some of our additional content like this 5.7 vs 6.4 HEMI comparison or 6.4 HEMI supercharger guide.

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30 Comments

  1. No noticeable difference in power when it should have dropped to 4 cylinders. Dealer says I won’t notice when it drops half it’s cylinders. Hard to believe, but otherwise very satisfied with it. Vehicle, on the whole, is far superior to the GM I had previously. Would have preferred a manual trans and No-spin rear, but can’t really complain. Well, one complaint. You wouldn’t believe where they put the CD player.

  2. Have a 2014 ram 2500 6.4 hemi… transmission rebuild at 50,000… long delay going into reverse… first symptom… week later check engine light. Is there a way to disable the MDS permanently? Right now using manual shift select. Works but not the best solution.

    1. You should be able to tune it out. Some of the tuners remove the GM mds. Look at some of the hand held tuners.

  3. 2011 Dodge Challenger srt8 392, rebuilt engine due to faulty lifters, know been in storage 14 months unable to find suitable lifters, very disappointing,
    So if any body knows of a good aftermarket lifters please contact me at Westfieldv8@gmail.con
    Thanks paul

  4. Bought a 2013 Challenger srt8, 73k miles lifters on left side went quickly…not sure what previous owner gave me, my mechanic told me someone had the head off before..very disappointed.. Having new crate motor installed!!!

  5. Have a 2015 ram 2500 with the 6.4 has 280000 miles only issue with the motor is over heating at random still has original trans and has been used to tow its whole life

  6. I have a 2016 Dodge Challenger Scat Pack Shaker which I now has almost 92k miles in under 6 years. It’s a daily driver and I just replaced the spark plugs (schedule says to replace them at 96k miles) which they all looked good for that mileage. Bottom line is the car still runs like new and looking to put another 90k+ miles on it.

    1. There are two ways on the Ram trucks. Using the Tow/haul mode, or use the shift paddle to indicate the top gear in place of D, i.e. 8 for the newer trucks…

  7. MY 2021 392 SCATPACK IS AWESOME, A GREAT INTER-STATE CRUISER. THE MDS IS A GREAT SYSTEM. DROVE FROM CLEVLAND, OHIO TO ROANOKE, VA., 900 MILES ROUND TRIP, RAN 80, 85 MPH FOR HOURS, FUEL ECONOMY WAS 24.5 MPG. NO COMPLAINTS HERE.

  8. 2012 jeep srt8, 167,000 miles and now I’m having misfires on cylinder 4 and a noticeable ticking sound, looking at replacing all spark plugs and lifter rollers. might even just trade it in for the new new.

  9. 2018 ram 2500
    Been thru 3 sets of brakes. Put a new thermostat in at 38k now transmission is over heating with no other notable issues, this truck has 55k (miles/us) on the odometer, got this truck in April 2019 wit 200 miles on it, check engine stayed on all the time, until 30k miles. It’s been nothing but problems for me. If It wasn’t for the fact my work owns this truck, (insurance, fuel, maintenance) I would have traded it in before the first oil change..

  10. Recently told by service. Manager that 0-40 Penn blend was all he used. Said he used what was recommended on filler cap. Cap said full synthetic. He still would not back down. My money walks. This was Wish new ski dealer I Huntsvill, TX. Beware

  11. I have the 6.4 hemi no ticks or lubre problems but then again i drove it normal and dont stomp the gas to race to the lif hu t eother i also let it watm up properly and dont just drive as soon as i start it plus i keep on the fluid changes and levels its a great very reliable engine you do all thos things

    1. I agree. I always let my vehicle warm up. Even in the summer I let it idle down before shifting out of park. Use oil it recommends and at 148,000 miles runs like new. 1 set of pads and rotors at 100,000 and a starter at 90,000. That’s it. Love the Ram

  12. I have a 2021 Ram 2500 6.4 hemi. Around 3000 miles the truck gas milage started dropping. I was getting around 11 mpg in town. It was down to getting 5 to 6 mpg. The engine started ticking and had a rough idle. At 4423 miles I dropped it off at the dealership. They called me a few days later and said that the oil had metal shavings in it. They replaced the long block and returned the truck to me. The truck now has about 5900 miles on it. My mileage is still 5 to 6 mpg and has a rough idle. I have about had it with this truck.

  13. I have a 2015 SRT 392 Challenger. Cam failed at 32k miles in March of 2020 right as it came out of warranty. Replaced cam and now currently at 49k miles. I was very disappointed at the way FCA handled my case especially since there was an extended warranty on my car.

  14. I have a set 2014 with a 6.4 has engine code with cylinder 7 misfire I have replaced all plugs still Thera your one have any idea ?

  15. own 2008 srt jeep 6.1 , lifter failure at 181,929 miles rebuild on motor, crank was fine , cam had to be replaced . runs great now

  16. 2021 RAM 2500 6.4 Hemi – 48,000 miles – 50-60% with 14-15K pound fifth wheel behind it. No issues of any kind. City MPG always bad. Hwy MPG 19 empty, 8-8.5 towing with cruise control, 9.5-10.5 towing without cruise.

  17. I got a 2013 chrysler 300 srt8 6.4 hemi white on red. Thing is a beauty. Always let it warm up properly before driving hard
    No problems beside steering pump and ac condenser due to a pebble hitting it . Just got a compliment today at the store as I was leaving about how nice the red seats were and how rare this car is. As I exited I light up the tires and went sideways in a cloud of smoke. It’s got 148,000kms I’m in Canada. I’ll never sell this thing .

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