For three years in a row, the Chrysler 3.6 Pentastar engine earned a spot as one of the top ten engines in the US market. It is hard to compete in such a category because the US Market is saturated with different engines – Inline fours, V6, V8, and many more.
Not only is it saturated, but you can say it is a sea of engines.
The 3.6 Pentastar engine must be quite different because, it managed to wade through them and snatch an award amidst the tight competition in the US market. It is deserving, and we are curious about what’s inside the engine?
What are Chrysler 3.6 Pentastar V6 Engines?
The Chrysler 3.6 Pentastar engine is part of the Chrysler Pentastar engine family, a series of die-cast aluminum cylinder blocks with a dual overhead camshaft design. The development of the 3.6 Pentastar engine started in 2010, but not until 2011 when it first appeared in public through the hoods of the Chrysler, Dodge, and Jeep Vehicles.
The 3.6 Pentastar engine was named “Phoenix” at the initial release but was later changed to another due to a conflicting trademark name. However, the Pentastar name was derived from a former signature of the Chrysler Corporation, dating back from 1963.
The rising of fuel prices prompted Chrysler engineers to develop an engine that would allow the usage of E85 or 87 octane fuel. Other features include direct fuel injection, dual variable valve timing, and cylinder deactivation.
The latter was also used in some vehicles as it increased the efficiency of the engine while running under different conditions.
Further, the innovations and technologies featured in this engine are one of the most technologically advanced engines created by Chrysler in the Chrysler lineup. Typical clients of the 3.6 Pentastar include the Dodge Challenger, Jeep Wrangler, Jeep Cherokee, and RAM 1500 – the most popular options.
Engine Specifications and Design:
- Production Run: 2010 – Present
- Cylinder Head Material: Aluminum
- Cylinder Block Material: Aluminum
- Configuration: V6
- Bore: 96.0 mm
- Stroke: 83.0 mm
- Valvetrain: DOHC four valves per cylinder
- Displacement: 3.6 L (3604 cc)
- Compression Ratio: 10.2 and 11.3
- Weight: 340 lbs.
- Maximum HP: 305 HP at 6,350 RPM
- Maximum Torque: 269 lb-ft at 4,175 – 4,800 RPM
Let’s take a look inside the engine!
Based on the design of the Pentastar family of engines, the 3.6 Pentastar engine has an open-deck design. This allows a lighter, cheaper, and more liberated engine production. In addition, the block has cast-iron cylinder liners for added strength.
The new 3.6 Pentastar engine is more powerful, more efficient, smaller, and therefore lighter.
You might wonder why automakers push a lighter material for production. Lighter material lessens the effort of the engine, and it also depends on the application. Some engines need to be in the middle or more on the heavy side.
But, for the lighter material, it is due to lightening up the load of the engine.
To proceed, the engine block has three piston oil cooling jets. And since there are six cylinders, one piston jet manages the temperature of two pistons. Temperature regulation is important to the reliability and longevity of the engine.
Beyond optimum temperature levels, the component may not perform according to its duty.
There are forged steel connecting rods, cast aluminum pistons with low-friction rings, and reduced skirt area for reduced friction and weight; a nodular iron crankshaft is also there.
The 3.6 Pentastar engine uses a vane-type, chain-driven variable displacement oil pump. Chrysler removed brackets for the engine accessories. The air intercooler, alternator, belt tensioner are bolted and bonded together by a serpentine belt. In this kind of setup, vibration and noise are reduced.
The cylinder heads are made from sand-cast heat-treated aluminum. A heat-treated material, like steel, becomes stronger after undergoing such a hardening process. Essential for resisting varying heat loads over time.
There are six cylinders in a 60-degree V-arrangement. Each cylinder features four valves per cylinder – two for each side. Dual overhead camshaft design with roller finger followers are chain-drive; hydraulic lifter actuates these valves.
The intake and exhaust camshafts come with torque-actuated phasers attached to the silent chain link-designed timing chains. The intake valves have a single-piece design with a forged austenitic head; the intake valve diameter is 39-mm.
Further, the exhaust valves, however, id a two-piece design with a 30-mm diameter.
The cylinder heads feature high-flow, high-pressure intake and exhaust ports and an integrated exhaust manifold. On top, you can see a lightweight composite intake manifold fitted with a 74 mm throttle body and electronically controlled multipoint port fuel injection system.
The maximum torque capacity of the engine was achieved across the RPM range – from 1800 to 6400 RPM. That means the 3.6 Pentastar engine can exhibit excellent torque display across the board without needing high-octane gasoline.
It is also bold on its stand with lesser fuel consumption, but efficient, low emission, smooth operation, and can be maintained easily.
The engine passed the environmental emissions test, even the most sensitive ones. The Federal Tier 2 BIN 5 emission requirements, Euro6 standards, and ULEV II (Ultra-Low Emissions Vehicle) standards.
The engine is also projected to pass the higher criteria of the LEV II and PZEV California standards.
In 2016, several years after its release, FCA released a modified and upgraded Pentastar engine family and a new 3.6 Pentastar version – appeared in Grand Cherokee and Dodge Durango.
It received a revision like a two-stage variable valve lift (VVL) providing low and high valve lifts.
The difference between the low and high lifts is that low lifts operate at low speeds, while the high valve lift for power-demanding conditions. Also, in the low lift setting, the engine saves about 2.7% more fuel than the predecessor.
The engine also has an exhaust gas recirculation system (EGR).
A new plastic manifold with longer runners, higher torque, high-tumble intake ports inside the cylinder heads, low-tension piston rings, and new valve springs. The fuel system management earned new eight-hole injectors and retained the port fuel injection.
All these improvements are made for a more efficient and emission-friendly engine.
Applications of the 3.6 Pentastar Engine:
- 2010 – Present Avenger, Grand Caravan, Routan, and Journey 283 HP
- 2012 – Present Jeep Wrangler 290 HP
- 2010 – Present Grand Cherokee 290 HP
- 2013 – Present Charger 300 HP
- 2010 – Present Dodge Challenger 305 HP
- 2013 – Present RAM 1500 300 HP
- 2015 – 2016 Chrysler 200 295 HP
- 2012 – Present Fiat Freemont, Lancia Thema and Voyager
Engine Tuning, Potential, and Modifications
If you opt to have your power and torque production increase, you might have to tune your engine. A performance gain depends on the tune you wanted. Some shops cater to different tuning setups.
But the minimum and common tuning include a 15 HP gain on 87 octanes, more than 25 wheel horsepower gain on a higher 91/93 octane, and more than 30 HP on E85 ethanol.
Apart from those, significant torque gains, in the mid-range perfectly suited for large size sedans; better throttle response and feel as well as smoother acceleration at different throttle positions; and an increase in fuel mileage.
Problems Surrounding the Chrysler 3.6L Pentastar Engine:
Competing with the most successful engines in the market is quite stressful. You have to exert your best every day, every time, and everywhere. However, putting too much stress on the engine may have negative consequences, especially if you fail to address the issue right away.
Add it with a bad habit of maintaining the engine; it’s the tail-end now. We put here a list of some issues with the 3.6 Pentastar. Please take note that this is not conclusive.
1. Cam Followers Issue
Commonly misinterpreted issue on the list. Since it is located in the cylinder heads, many owners are confused with it. Mind you that for this particular issue, FCA issued a service bulletin.
However, some engines have the same issue, but it is not totally fixed. If you noticed any ticking or tapping sound from the upper engine area, it might be a cam follower issue.
2. Faulty Cylinder Heads
In connection to the cam follower issue, cylinder heads are also prone to failure in this engine. The left side of the cylinder head caused the problem, mainly the valve seats in cylinder number two.
However, the automaker already resolved the issue in mid-2013 by redesigning the valve guides and seats.
Thanks to Fiat-Chrysler for their patience in extending the 3.6 Pentastar warranty to ten years for the left cylinder heads on 2011 to 2013 models.
3. Cooling Systems and Oil Pumps
The water pump and radiator of the 3.6 Pentastar engine might also be a problem. Some sand remnants are still sitting there since the heads and other components undergo a tedious sand-casting method.
If not properly cleaned before the assembly or installment, the sand deposits may find its into the cooling system and cause sludge in the cooling system.
Some owners also complain about clogged-up radiators and short-lived components like water pumps, oil coolers, thermostats, etc.
If you are talking about reliability, fuel efficiency, fuel economy, low emissions engine, you are pointing to the 3.6 Pentastar engine. The engine that competed against the technologically advanced 2.0 Turbo Hurricane.
But, you might think that the Pentastar is inferior; well, let the facts speak to you.
In its staggering lineup, the 3.6 Pentastar engine is worthy in its price. Chrysler made this engine as one of their technologically advanced engine presently. There is so much this engine can offer, and we might see more innovations and upgrades.
I hope we can hear more in the future about Chrysler’s plan for the 3.6 Pentastar engine.