2014-2019 Charger, 300 & Challenger 3.6L Pentastar V6 AWD: Problems, Identification, and Used Replacement

Identifying the Correct 3.6L Pentastar AWD Engine

The 3.6L Pentastar V6 engine used in 2014-2019 Dodge Charger, 2014-2019 Chrysler 300, and 2017-2019 Dodge Challenger All-Wheel Drive (AWD) models is a specific variant that cannot be swapped with engines from Rear-Wheel Drive (RWD) or Front-Wheel Drive (FWD) vehicles. Making a positive identification before purchase is critical.

Key Identification Checks:

"Classic" vs. "PUG" Pentastar

The engines in these specific 2014-2019 AWD models are the original, or "classic," Pentastar design. Starting in 2016 on some other Chrysler, Dodge, Jeep, and Ram models, an updated version known as the Pentastar Upgrade (PUG) was introduced. The PUG engine features a cooled Exhaust Gas Recirculation (EGR) system and a two-stage Variable Valve Lift (VVL) system for improved efficiency. This AWD engine is the classic, non-EGR, non-VVL design. The two are not interchangeable.

Common Failure Symptoms

A failing 3.6L Pentastar will often provide clear warning signs. If you experience these symptoms, a mechanical inspection is necessary to confirm if the engine assembly is the root cause.

• "Pentastar Tick": A sharp, rhythmic ticking or tapping sound coming from the upper part of the engine (the valve covers). The noise is often loudest on a cold start and may quiet down as the engine warms up. This is a classic symptom of worn rocker arms.
• Engine Knocking: A deeper, heavier knocking sound from lower in the engine can indicate severe wear on internal parts like connecting rod bearings, often caused by oil starvation or contamination.
• Overheating: While often caused by failing water pumps or thermostats, persistent overheating can cause permanent engine damage, such as warped cylinder heads.
• Low Oil Pressure Warning: This can be triggered by a faulty sensor, but it may also signal a failing oil pump or excessive internal wear causing a loss of pressure.
• Misfire Codes and Rough Running: Fault codes like P0300 (Random/Multiple Cylinder Misfire) accompanied by a rough idle or hesitation can point to internal mechanical problems, such as a failed lifter or loss of compression.

Diagnostic Flowchart

Known Problems, TSBs, and Recalls

This engine family has several well-documented issues. When inspecting a used engine or diagnosing your current one, be aware of these potential faults.

The "Pentastar Tick" (Rocker Arm / Lifter Failure)

This is the most widely known issue, affecting models from 2014-2020. The problem stems from premature wear of the roller bearings on the rocker arms, which are crucial components in the valvetrain. When these bearings fail, they can damage the camshaft lobes and send metal particles through the engine's oiling system, leading to further damage. A class-action lawsuit was filed concerning this issue, alleging that defective rocker arms and lifters could lead to ticking noises, misfires, and eventual engine failure. The only remedy is to replace the worn rocker arms and any damaged lifters or camshafts.

Oil Filter Adapter / Oil Cooler Housing Leaks

The original oil filter and cooler housing is made of plastic and is mounted in the "V" of the engine, underneath the intake manifold. Over time, the plastic can crack or the seals can degrade from heat cycles, causing significant oil leaks that pool in the engine valley or drip down the back of the engine. The recommended fix is to replace the entire housing assembly. Many owners opt for an upgraded aftermarket aluminum housing to prevent future failures.

Spark Knock (2019 Models)

Some owners of 2019 models may experience a spark knock (pre-detonation) sound during acceleration. This issue is addressed by a Powertrain Control Module (PCM) software update. TSB 18-106-20 and TSB 18-107-20 instruct dealers to reprogram the PCM with the latest software, which adjusts engine parameters to eliminate the noise.

Alternator and Driveshaft Recalls

While not direct engine failures, related recalls are important. Certain 2014 models with a 160-amp alternator were recalled because the alternator could suddenly fail, causing the vehicle to stall (Recall P60). Additionally, 2014-2017 AWD models were recalled because the front driveshaft bolts could loosen, leading to a loss of power (Recall T03).

Repair or Replace?

Deciding whether to repair your current engine or replace it with a used unit depends on the severity of the failure.

• Oil Filter Adapter / Oil Cooler Housing Leaks: Always repair. This is a common, manageable repair. The leak is external and does not cause internal engine damage if caught early. Using an upgraded aluminum housing is a permanent fix. Typical shop costs range from $800 to $1,900, while DIY parts cost $250 to $400.
• The "Pentastar Tick" (Early Stage): Repair makes sense when the issue is caught very early, before the failing rocker arm's roller bearing sends metal shavings throughout the engine. If there is no ticking noise and metal is only found in the oil filter, replacing all rockers, lifters, and inspecting cams is viable. Typical shop costs range from $2,000 to $5,500+, while DIY parts cost $600 to $1,200.
• Severe Rocker Arm Failure or Bearing Damage: Replacement is the smarter choice when a rocker arm failure has been left unchecked, leading to an audible tick, misfires, and camshaft lobe damage. At this point, metal particles have likely circulated through the oiling system, compromising the crankshaft bearings and oil pump. Attempting a top-end repair on an engine with a contaminated bottom end is extremely risky.
• Catastrophic Failure: In cases of severe overheating, a blown head gasket that mixes oil and coolant, or catastrophic bearing failure, replacement is the only practical option.

Replacement Cost Estimates

The cost to replace a 3.6L Pentastar engine varies based on the type of replacement unit. Used units typically run $1,500 to $3,200. These prices are estimates and do not include taxes or shipping.

What Fails at Every Mileage Band

Under 60,000 Miles

Engines in this range are generally healthy, but premature "Pentastar Tick" from rocker arm bearing failure can occur due to oiling issues or part defects. Early failure of the plastic oil filter/cooler housing is also possible, causing oil or coolant leaks. Cylinder head failures (misfires on a specific cylinder) have been reported, though less common than on pre-2014 models.

• ✓Do during install (required): Replace the plastic oil filter/cooler housing with an upgraded aftermarket aluminum unit to prevent future leaks.
• ✓Do during install (required): Replace all required consumables, including oil, oil filter, coolant, intake gaskets, and the single-use Torque-to-Yield (TTY) crankshaft bolt.
• ✓Do during install (recommended): Replace spark plugs (due at 100,000 miles, but labor is free now) and the PCV valve.
• ✓Cheap insurance while the engine is out: Carefully inspect the valvetrain for any early signs of the "Pentastar Tick" or unusual wear on camshaft lobes and rocker arms.

60,000 - 100,000 Miles

Leaking plastic oil filter/cooler housings become a very common failure point in this mileage range, leading to oil pooling in the engine valley. The "Pentastar Tick" due to rocker arm bearing failure is highly prevalent, often leading to camshaft damage if not addressed promptly. Failures of cooling system components like the water pump and thermostat begin to appear.

• ✓Do during install (required): Replace the original plastic oil filter/cooler housing with an aluminum aftermarket version.
• ✓Do during install (required): Replace spark plugs and all intake gaskets.
• ✓Do during install (required): Replace all required consumables (oil, filter, coolant, TTY bolt).
• ✓Do during install (recommended): Proactively replace all 24 rocker arms and associated lifters with the latest Mopar revision parts. This is considered critical cheap insurance as the engine is already out.
• ✓Cheap insurance while the engine is out: Replace the water pump, thermostat, and serpentine belt.

100,000 - 150,000 Miles

Failure of the original plastic oil filter/cooler housing is almost an inevitability if it hasn't been replaced already. Rocker arm failure is extremely common. Mechanics and experienced owners suggest planning for replacement around 100,000 miles as a standard maintenance item. Wear on timing chain guides and tensioners becomes a possibility.

• ✓Do during install (required): Replace all 24 rocker arms and lifters with updated parts.
• ✓Do during install (required): Replace the oil filter/cooler housing with an aluminum unit.
• ✓Do during install (required): Replace spark plugs, PCV valve, water pump, thermostat, and serpentine belt.
• ✓Do during install (required): Replace all required consumables (oil, filter, coolant, gaskets, seals, TTY bolt).
• ✓Cheap insurance while the engine is out: Inspect the timing chain, plastic guides, and tensioners for wear. Consider replacement given the mileage and accessibility.

Over 150,000 Miles

At this mileage, survival depends heavily on previous maintenance. Failures are typically the same known issues (rocker arms, oil cooler) if they were never addressed. There is an increased likelihood of wear on timing components, including chain stretch and broken plastic guides, as well as general wear on sensors, seals, and cooling system components.

• ✓Do during install (required): Perform all items listed in the "100,000 - 150,000 Miles" band. Assume all common failure parts are at or beyond their service life.
• ✓Do during install (recommended): Replacing the timing chain, guides, and tensioners is no longer preventative but a practical necessity for a reliable installation.
• ✓Cheap insurance while the engine is out: Replacing the oil pump. While not as common a failure, its replacement is wise while the engine is out and disassembled to this degree.

Real Owner Experiences

The following table highlights real-world repair scenarios and costs reported by owners of vehicles with the 3.6L Pentastar engine.

Freight & Delivery Reality

When ordering a used 3.6L Pentastar engine, it will not arrive in a cardboard box via standard parcel delivery. A fully dressed engine assembly weighs approximately 530 lbs and measures roughly 48" x 40" x 38" before crating. It ships as Less-Than-Truckload (LTL) freight on a wooden pallet.

If you are having the engine delivered to a residential address or a shop without a loading dock or forklift, you must request a truck with a liftgate to lower the pallet to the ground. Always inspect the engine thoroughly before signing the delivery receipt. Look for damage to the plastic intake manifold, valve covers, or the delicate cast-aluminum oil pan that may have occurred during transit.

Installation & Programming

Installing the AWD 3.6L Pentastar is an advanced-to-expert level job, typically requiring 12 to 32 hours of labor. The process involves specific tools and procedures that cannot be skipped.

Required Tools

• Camshaft Phaser Lock / Timing Chain Holder Tools (Mopar #10200A, #10202, and #10369A)
• Crankshaft Pulley Puller / Harmonic Balancer Puller (Mopar #10263)
• Calibrated inch-pound torque wrench
• Engine hoist and engine stand
• Dealer-level scan tool (like wiTECH) for programming

Consumables Needed

• 6.0 quarts of OE-spec 5W-20 or 5W-30 full synthetic oil
• Premium oil filter (Mopar #68191349AC)
• Mopar-approved OAT Coolant meeting MS-12106 specification
• Upper and lower intake manifold gaskets, thermostat housing gasket, front and rear crankshaft main seals
• 6 new OE-spec double platinum or iridium spark plugs (gap to 0.043 in)
• High-quality RTV sealant (Mopar Threebond or Permatex Ultra Grey)
• New PCV valve
• New Torque-to-Yield (TTY) Crankshaft Damper Bolt (Mopar #06509873AA)

Installation Gotchas

Warning: You must pull the front CV axle and slide the intermediate shaft completely out of the oil pan before lifting the engine to avoid cracking the pan.

Warning: The Torque-to-Yield (TTY) crankshaft damper bolt stretches when tightened and must never be reused. Always replace it with a new bolt.

• Delicate Oil Cooler Torque: Torque the mounting bolts to exactly 106 in-lbs (9 ft-lbs) in sequence to avoid cracking the plastic housing.
• Magnetic Timing Wheels: The timing wheels are highly sensitive to magnetic fields; keep them away from magnetic tools.
• Interference Engine: Do not rotate the crankshaft or camshafts independently while the timing chains are off, or the valves will hit the pistons.
• Camshaft Cap Torque: Camshaft bearing caps have a very low torque spec (approximately 84 in-lbs).
• Wiring Harness: You must reuse your original engine wiring harness to ensure all pinouts, accessory connectors, and vehicle-specific options match.

Programming Requirements

After installation, programming is mandatory. A Crankshaft Position (CKP) Sensor Relearn procedure must be performed to prevent misfire codes. Additionally, the vehicle's Powertrain Control Module (PCM) requires security marriage. This involves writing the VIN to the replacement engine and syncing the security keys using a dealer tool like wiTECH to prevent the anti-theft system (SKIM/WIN) from locking the vehicle.

Questions to Ask Your Installer

Before handing over your vehicle, ask your mechanic these specific questions to ensure they are qualified for this exact engine swap:

• Have you worked on the AWD Pentastar before and are you aware of the process for removing the front CV axle and intermediate shaft from the oil pan?
• Will you be using a new, one-time-use Torque-to-Yield (TTY) crankshaft damper bolt?
• What is your process for the Crankshaft Position (CKP) Sensor Relearn and the PCM security marriage/VIN write?
• Will you be inspecting the replacement engine's rocker arms and camshafts for wear before installation?
• Do you have an inch-pound torque wrench and will you follow the specific 106 in-lbs sequence for the oil cooler housing?
• What brand and type of oil, coolant, and gaskets will you be using for the installation?
• Does your quote include all necessary fluids, gaskets, seals, and spark plugs, or are those extra?
• What warranty do you offer on your labor and on the used engine itself?

Arrival Inspection: Compression and Leak-Down

When your used engine arrives, test the cylinders before installing it. A healthy 3.6L Pentastar V6 should show consistent compression across all six cylinders. The readings should be within 10 to 15 percent of each other. You should also perform a leak-down test (pumping compressed air into the cylinder to see how much escapes). A good used engine will have a leak-down rate of less than 15 percent. If air leaks heavily into the crankcase or exhaust, it means the piston rings or valves are worn.

Before the First Start: Fluids and Priming

Never start a used engine dry. Sitting on a shelf drains the oil from the moving parts. You must prime the oil system (build oil pressure before the engine actually fires) to prevent permanent damage.

1. Add Fresh Fluids: Install a new oil filter. Fill the engine with fresh 5W-20 engine oil that meets the Chrysler MS-6395 standard. Fill the cooling system with Mopar OAT (Organic Additive Technology) coolant (MS-12106 spec, typically purple). Do not mix this with older orange or green coolants, or it will turn into a thick gel.
2. Disable the Fuel or Spark: Remove the fuel pump relay or unplug the ignition coils. This stops the engine from starting while you turn the key.
3. Crank the Engine: Turn the key and crank the starter for 10 to 15 seconds. Watch the oil pressure gauge on your dashboard.
4. Rest and Repeat: Let the starter cool for one minute. Crank the engine again for 10 to 15 seconds. Repeat this process until the gauge shows steady oil pressure.
5. Start the Engine: Reconnect the fuel pump relay or ignition coils. Start the engine normally and listen for any unusual noises. Check for leaks immediately.

Long Block vs. Complete Assembly

When shopping for a used 3.6L Pentastar engine, you will usually see two choices: a long block or a complete assembly.

A long block includes the heavy metal engine block, the cylinder heads, and all internal moving parts like pistons and camshafts. It is stripped of external bolt-on parts. If you buy a long block, you must move your old intake manifold, exhaust manifolds, fuel injectors, and sensors to the replacement engine.

A complete assembly usually includes the engine block and heads, plus the intake manifold, exhaust manifolds, fuel rail, and throttle body left attached.

If you buy a long block, pay close attention to the oil filter housing (also called the oil cooler) located in the "V" shaped valley between the cylinder heads. This plastic housing is famous for cracking and leaking oil or coolant. It is highly recommended to install a brand-new oil filter housing and new intake manifold gaskets rather than reusing your old ones.

Frequently Asked Questions (FAQ)