3.7 Magnum PowerTech Common Engine Problems

The 4 Most Common Dodge 3.7 PowerTech V6 Engine Problems

Jake Mayock

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Jake is a founder of 8020 Media and TuningPro. He has over a decade of experience in the automotive industry including parts sales, writing, DIY modifications & repairs, and more. Jake is currently converting his N54 to a single turbo and building a Miata track car. He’s an experienced, hands-on automotive enthusiast who delivers in-depth, well-researched content.

While some love the Chrysler PowerTech engines, the 3.7L V6 doesn’t have a very good reputation. Not only is the engine known for being underpowered and inefficient, but it also suffers from some potentially catastrophic engine problems. Some of the most common problems include the valve seats, lifters, piston rings, and PCV valve. In this article, I discuss these Dodge 3.7 PowerTech engine problems, symptoms, and overall reliability.

Dodge 3.7L PowerTech Problems

  • Valve Seat Failure
  • Stuck Lifters / Lash Adjusters
  • Piston Ring Landings
  • PCV Valve

1) Valve Seat Failure

Dodge 3.7L PowerTech Valve Seat Failure

Valve seats sit within the engine head and are responsible for keeping both the exhaust and intakes valves fully sealed shut when they are closed. When one of the valves is closed, the head of the valve rests against the valve seat.

When a valve seat fails it can prevent the valve from fully closing which will break the airtight seal that helps maintain cylinder compression. With that being said, the end result is a loss of compression within the cylinder. When a cylinder has low compression, when air will leak out of the cylinder as it tries to compress air, essentially making the whole cylinder ineffective. This will have serious performance implications but can also create additional engine problems if left alone for too long.

On the 3.7 PowerTech, valve seat failure is most commonly caused by excessive engine heat. Excess engine heat can warp the metal the seat is made of and therefore cause it to pop out of its position.

3.7 Magnum Valve Seat Failure Symptoms

  • Loss of engine compression
  • Loss of power
  • Lack of acceleration
  • Poor overall performance
  • Cylinder misfires

When a valve seat fails on V6 Magum’s it is usually only isolated to one cylinder. Fortunately, one cylinder losing compression does not cause the other cylinders to lose it too; it is isolated to the one cylinder with the failed seat.

Having only one cylinder go bad can actually make it difficult to detect the problem in the first place. Your engine’s power will virtually be running on 5 cylinders instead of 6 which might not be very noticeable from a performance perspective if you don’t get on the throttle ever.

Misfires will likely be the most common symptom. If you have misfires and replace your spark plugs and ignition coils, your next step should be to do a compression and leak-down test on all the cylinders.

Valve Seat Failure Replacement

Since the valve seats are pressed directly into the cylinder head, your only replacement option here is to rebuild or completely replace the cylinder head. You’re likely going to run into a $1,000+ repair bill whether you choose to replace or rebuild the existing head. DIY’ing the repair is likely a no-go unless you are a trained machinist.

One of the best prevention tips is to make sure your engine never overheats. Heat kills valve seats so keep an eye on engine temps and if you begin to shoot over normal temps, pull over and shut your engine off. Keep your engine fresh on coolant and flush/replace the coolant as recommended. If you have power mods on your engine you can consider adding some cooling modifications but I don’t recommend that for stock engines.

2) Stuck Lifters / Lash Adjusters

The 3.7 Magnum is a single overhead cam engine (SOHC). Because the camshaft in overhead cam engines is located in the cylinder head, they do not technically have lifters. However, the 3.7 Magnum does have hydraulic valve lash adjusters which function similarly to traditional lifters.

Lash adjusters are mounted in the head and are responsible for maintaining zero clearance between the cam follower and the valve, whereas traditional lifters maintain a small amount of clearance. Here is an article all about valve lifters in case you want to learn more.

In the 3.7L Dodge Magnum engine, the lash adjusters are prone to becoming stuck. Oil issues are the common cause of this problem. If you run oil that is too thick, or go a prolonged period of time without an oil change, the lash adjusters can fall out of place. When this happens, the valve will get stuck from opening and closing which will cause major performance issues and other sporadic engine problems.

Symptoms of Stuck Lash Adjusters

  • Typical lifter tick engine noise
  • Cylinder misfires
  • Loss of power, lack of acceleration
  • Rough idling

Lash Adjuster Replacement Options

If you have a stuck lash adjuster the only replacement option is going to be to replace the lash adjuster. When this problem develops, it generally is isolated to one cylinder, so you can get away with simply repairing the single cylinder. However, if your mechanic is already down there, we would recommend replacing the full set. A single lifter will run about $10-$25 for an aftermarket brand or the alternative option is to upgrade to a high-performance set which will run you closer to $100 per lifter but provide more reliability.

3) Piston Ring Lands

3.7 Magnum Piston Ring Landings

Piston heads have rings or grooves on them, as seen in the picture above, which are responsible for sealing the piston against the cylinder wall. These rings, also called ring lands, hold an airtight seal against the cylinder wall.

On the 3.7L Magnum or PowerTech, the ring lands have an inherent design flaw that causes them to produce excessive heat within the engine. In addition, the engine has rather small oil drain holes which further exacerbate the heat problem. Excess heat can break down oil, causing it to gunk up and get stuck within the engine. This is the main reason why the lash adjusters get stuck as we discussed in the previous engine problem.

Excessive heat can lead to numerous performance implications and also cause serious internal engine damage. Additionally, it can cause a number of other engine support systems to fail.

Dodge and Jeep Excess Heat Implications

Here is a list of problems that can occur when an engine is exposed to excessive heat for prolonged periods of time:

  • Major metal engine components like the head, pistons, valves, etc. can warp, causing complete engine failure
  • Cooling system components like hoses, tanks, radiators, etc. can develop leaks and leak coolant, leading to even more engine heat
  • Oil leaves sludge in the engine causing lash adjusters to get stuck
  • Oil burns more quickly, leading to excess oil consumption which can cause internal components to rub against each other from lack of lubrication

I want to point out that this isn’t an overly common problem. The severity of the problem usually causes it to be blown out of proportion on the internet. However, it has happened enough for leading companies, such as Powertrain Products, to call out Chrysler for the inherent issues. Chrysler has stood behind their engine throughout the complaints.

Powertrain Products suggests that this can occur as early as 75,000 miles on the 3.7L PowerTech / Magnum. Alternatively, we have read plenty of stories of these engines lasting well beyond 200,000 miles without any issues.

4) Positive Crankcase Ventilation (PCV) Valve

When an engine burns fuel it produces waste gases. Most of these gases are passed through to the exhaust system where they are further burned before flowing out of the exhaust into the atmosphere. However, some of these gases get trapped and can make their way down into the crankcase which holds oil at the bottom of the engine.

The PCV valve is attached to the crankcase and is responsible for releasing any excess gases that make their way into the crankcase. However, over time the valve can be gunked up from these gases and cause the valve to no longer open or vent the gases out.

When this happens, the gases get trapped in the crankcase which can gunk up the oil and make it sludge-like. When this happens, it can cause oil leaks throughout the engine and ruin seals, gaskets, etc., and lead to leaks through things such as the valve cover.

PCV Valve Failure Symptoms

  • Rough idling
  • Loss of power, poor performance
  • Engine hesitation, sputtering
  • Poor fuel economy
  • Oil leaks (gaskets, seals, valve cover, etc.)

PCV Valve Replacement Options

Fortunately, replacing the PCV valve is a relatively inexpensive and simple fix. When you replace the PCV valve we also recommend doing an oil change to flush out any potentially bad oil within the engine.

The PCV valve itself is about a $15 part and can be DIY’ed by most people with basic engine knowledge. Here is a DIY video of the PCV valve replacement on a Ram 1500:

Chrysler, Dodge, Jeep 3.7L Reliability

Is the Magnum 3.7L reliable? The engine, along with its 4.7L brother, doesn’t have the best reputation on the internet. There are some serious issues such as the valve seats and lash adjusters that can cause catastrophic engine failure. However, these problems aren’t quite as common as they might be made out to seem.

The biggest issue that causes problems on the 3.7 is excessive engine heat. Making sure your engine never overheats or runs hot is crucial to maintaining reliability. Change the oil frequently, flush the coolant per the recommended maintenance schedule and you shouldn’t run into any catastrophic issues. Some items we didn’t mention that are semi-common are things such as head gaskets and valve cover leaks, and water pump failure. All of these problems are caused by excess heat so preventative maintenance of the cooling system is key to maintaining reliability.

Some engines will report major issues as early as 75,000 miles while we have also read plenty of posts of the 3.7 Magnum lasting well beyond 200,000 miles and even into 300,000 miles. Overall, when properly maintained, these engines should be good for at least 200,000 miles. 

If you are overly concerned about major problems, you can upgrade various parts of your cooling system, such as the radiator, to make sure excess heat doesn’t plague your PowerTech.

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11 Comments

  1. I’m loosing coolant but I don’t see any leaks and the engine is running hot. I have a Jeep Liberty 3.7 .

  2. Yes mine has a problem with crank bearing issues it’s a renegade 2003 bottom noise thanks again any help would be appreciated thank you cheers the jeep has 240 kon the clock

  3. Unfortunately, we’ve had engine failure in 2 2008 Dodge Nitros with the 3.7 motors. Both were used vehicles when purchased, the 1st with unknow history, but the 2nd was family friend and came with complete service records. The 2nd one’s failure came with no notice – motor stopped running driving down the road – 150,000 miles on OD.

    1. Just bought a 2007 1500 quad cab. When I test drive it, I could have sworn it was a big V-8 engine. It was powerful. Turned out to be the 3.7 magnum engine. It has 240,000 miles and runs GREAT!!! I did a full tuneup and runs even better. Very happy with the beast. Tires and brakes will be next.

  4. I’ve had a head gasket leak with my 2006 Jeep Liberty at 243,000 mi. Up to that point the engine ran perfect, I always change oil at 5000 mi. But the water pump failed without warning, it had no leaks or noises. One cold morning I warmed the engine up before leaving for work. About 2 miles from the house I noticed that the heater wasn’t putting out, the temperature gauge was straight up in normal range. I decided to change the engine, because of the number of miles on the lower end. The salvage yard engine from 2007 Dakota with 157,000 mi. is running fine so far, having put 20,000 on it. Flush the cooling system once a year, that iron engine block produces a lot of rust that clogs things up, and change your oil by 5000 mi. every time.

    1. That’s great to hear! I’ve got 2006 Dakota 3.7 that’s blowing, in my opinion white smoke but in my mechanic’s opinion, he says blue smoke. I hope for the blue believe me, lol! I pay my truck off in just 5 payments so God knows I want this truck to be in good timing order for another 100k. I’m hitting the 185k mark soon so I do understand that repairs will be having to be made & I’ve recently have been repairing some things but this smoke thing has me kinda stumped. My mechanic & I will be looking at it more in depth on Monday. Wish my pocket book luck y’all!! 🤞

  5. Unfortunateely, your information on the PCV valve and the crummy YouTube fixit show is off base. Dodge Dakotas and the Ram 1500 with the 3.7 engine have have a very difficult replacement for a PVC Valve that the You Tubber “mechanics” never address. Reason: The PCV Valveis buried in the far rear drivers side up close to the firewall. Furthermore, to unscrew the valve wire bundles interfere with its service along with the need for a 34mm deep socket to remove the valve.

  6. glad I read this- I almost bought a 2008 Dodge Ram 1500 with the 3.7 V6 with 140k – I doubt it would go to 160k without one of the aforementioned excessive heat issues plaguing them- the Seller wants $8000- it looks awesome- but looks can be deceiving- guess I am going back to 2001 F 150 V6 or a Toyota Tacoma V6- I only get one chance – when your moneys gone – its gone- Let’s face reality

  7. Wife traded her SUV, Chevy, for a 07 Nitro 3.7. She drove it 1 week and on her way home stopped at dollar general. When she came out she thought the battery was dead because it just clicked. I towed it home and assumed that starter was bad, replaced it and same thing. I tried turning the crank, and it would only turn 3/4 a revolution and then hangs up like something wedged is stopping it from turning full resolutions! I haven’t got the head off yet, but I pulled number 1 cylinder spark plug, last! ND it was bent and the ceramic was broken, plus the spark igniter, for fire, was completely bent around the opposite direction! I’m worried!

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