If you’ve bought a Chrysler, Dodge, or Jeep vehicle made since 2011, there’s a decent chance that you went home with a Chrysler 3.6L Pentastar engine. The engine has seen use across a number of vehicle models, giving the machinery thorough real-world testing that helps identify the most common issues to expect.
The Chrysler 3.6L Pentastar Engine
Fiat Chrysler Automobiles (FCA) debuted the Pentastar in 2011. The six-cylinder engine has dual overhead cams and a multivalve system with four valves per cylinder and variable valve timing (VVT). Its use quickly expanded into other vehicle models and has continued to this day.
Dodge included the engine in the Challenger, Charger, Durango, Grand Caravan, and Journey, as well as the closely related RAM line of pickups and vans. Chrysler put the Pentastar into the Town and Country, 200, 300, Pacifica, and Voyager. Jeep’s list is shorter, including just the Grand Cherokee, Wrangler, and Gladiator.
Performance varies slightly depending on the flavor of Pentastar. For example, the Pentastar on the 2022 Jeep Wrangler provides 285 HP and 260 lb-ft of torque. Chrysler overhauled the engine in 2016, improving several components of the engine. These changes lowered the weight of the block while providing similar performance numbers at 295 hp and 260 lb-ft of torque.
Common Jeep 3.6 Engine Problems
Below are some of the most common 3.6 Jeep engine problems. Note that problems from other systems are excluded, such as the V62 fuel pump relay recall that only affected Dodge Durangos and Jeep Grand Cherokees from the years 2011 to 2013.
Be sure to check any vehicle you look at for all potential issues before committing to a purchase.
Problem 1: Overheating
In this section, we’ll discuss the most common reasons your Jeep 3.6 Engine is overheating. And the solutions are in the next section.
Reason 1: The radiator fins or cooling tubes are clogged
The radiator works as the heat sink for your vehicle. So, it’s a must to ensure that the radiator, coolant hoses, and the relevant tubes are clog-free. If the coolant cannot circulate properly, the engine may overheat.
Solution: Clean the radiator fins and relevant tubes
Inspect the radiator fins, related hoses, tubes, and even the fan blade for damage. Then, clean them when necessary or replace them if there’s no other option.
Also, turn the engine off and check whether the fans spin with the engine off (the fans keep spinning to prevent your engine from overheating). If the fans stop working, you might need to replace the entire fan assembly unit (sadly).
Reason 2: Faulty thermostat
For being dual-purpose, the thermostat opens up and closes now and then. For the on-and-off nature of the thermostat, it wears and tears over time. You’ll notice strange engine noises, poor engine performance, and high-temperature readings when the thermostat is not doing great.
Solution: Replace the faulty thermostat
Thermostats are prone to get stuck over time. And, when it happens, the coolant cannot reach the radiator which causes the engine to overheat.
Here’s how you can replace a faulty thermostat:
- Locate your thermostat first. Then, take a bucket and place it under where you’ll be working (it’s for catching the fluid that will be escaping while working).
- This time, remove the clamp and pull off the hose.
- Inspect the bolts that help your thermostat to be in place. Then, get rid of the bolts and you can lift out the old thermostat.
Yes, that’s it.
Reason 3: Low coolant level
The coolant of your vehicle helps prevent corrosion in the cooling system. But if it leaks or gets damaged over time, the engine can be excessively hot.
Check for other signs like the car heater isn’t working, the coolant level sensor is faulty, the overflow reservoir is empty, the temperature gauge is fluctuating, and a sweet-smelling odour under the hood. These signs also indicate that you should take action for low coolant levels.
Solution: Top up the engine coolant
Topping up the engine’s coolant might not be the solution always since there are other issues related to it. You should seek professional help if you think that the coolant needs to be repaired or replaced.
However, here’s how you can top up the engine coolant:
- Find where the coolant reservoir is located. Read the car handbook to know the right information about it.
- Open the reservoir cap covering it with a cloth (because there can be some residual pressure in the system).
- Now, fill the coolant and slowly top it up to the maximum level.
- Finally, screw back the cap until you hear a click.
And, you’re done!
Reason 4: Head gasket failure
In most cases, the engine overheats for low coolant levels but there are times when it happens even during the coolant is full. In that case, your jeep might have blown the head gasket.
Solution: Replace The Blown Gasket or Use a Sealer
To fix a blown gasket, you need to replace it with a new one. Replacing the failed gasket would be the best option but still, it’s a lengthy procedure and complex as well.
There are alternative options. You’ll find high-quality head gasket sealers on the market that will re-seal a leaking head gasket. Using the sealer doesn’t require following any complex steps; you need to add it to the cooling system.
However, make sure you read the product instructions carefully because some sealers are designed to be added directly to the cooling system and some require flushing and filling the cooling system. So, read first and be sure what to do.
Reason 5: Faulty water pump
The water pump must be stable because it’s the cooling system component of your vehicle that controls the coolant’s flow. Internal contamination, erosion, electrolysis, and abrasive particles are the common reasons why the water pump stops working.
Solution: Remove the water pump or use a sealer
Removing a leaky water pump is a complex process like the previous case. Here’s a brief of the steps you’ll need to follow:
- If the cooling system is dirty, flush it.
- Drain the coolant and get rid of all the engine belts.
- Get rid of the other components so you can access the water pump bolts.
- This time, remove your water pump.
- Finally, you need to replace the gasket and install a new pump.
If this is not what you want, you can use seal-fixing products to resolve a leaking water pump in an easier way.
Reason 6: Heater core issues
A leaked heater core can result in low coolant levels. Also, if there are both heater core problems and water pump failures exist in the vehicle, the engine will overheat.
Solution: Replace the failing heater core
Fixing a failed heater core requires professional help. It’s best to get help from a mechanic who can diagnose the issue and take appropriate action. The replacement process is not only time-consuming but also requires removing the dashboard and other components as well.
Problem 2: Rocker Arm Wear and Tear
The rocker arms are part of the engine’s valve assembly, assisting with the opening and closing of the intake and exhaust valves.
When the rocker arm breaks or gets loose, the exhaust & intake valves don’t function correctly. Also, the cylinder connected to the damaged rocker arm gets disabled. Eventually, it will limit your engine’s performance and question the safety of your driving experience.
Below are the most common symptoms of a damaged rocker arm:
- Ticking noises
- Physical deterioration
- Weak engine performance
Solution: Replace the damaged component
First off, inspect the rocker arms as well as its surrounding parts when the engine is running. Check the symptoms and you might hear the noises, or notice the engine stalling.
If you notice the ticking or clicking noises, lubricating the moving parts, wor camshaft lobes, and warped valves would help. But if you experience poor acceleration, or engine stalling while driving, things might not change unless you replace the broken or damaged component.
Physical deterioration of the rocker arm is easy to indicate; I mean, it’s just about the visual inspection. Get rid of the valve cover and inspect whether the pivot point and valves are in poor condition.
If you find something unusual, replace the degraded rocker arms.
Problem 3: Cylinder Head Damage
Cylinder heads sit on top of the engine’s pistons, forming the main combustion chamber.
If the cylinder heads become cracked or otherwise damaged, the engine can leak fluids, misfire, drop performance, overheat, and start smoking. Overheating of the valve seats on the cylinder also causes major damage to the cylinder head.
The damage is more common in engines that are produced between the 2011 to 2013 production years of Pentastar. Most cylinder heads of these productions had defects, resulting in an extension of the warranty specifically for that cylinder head in those model years.
Solution: Replace the cylinder head
A damaged or overheated cylinder head can leak oil which may result in more damage to the pistons, engine, and cylinder bore. If you smell oil leaking onto the exhaust anytime, it’s a clear sign that you have a cylinder head failure.
Unfortunately, the only fix for a damaged cylinder head is to replace it. Also, the replacement is costly as well. The average expense for replacing a cylinder head is $2,000-$3,000 but it varies on whether you take mechanical help or do it yourself.
In January of 2022, plaintiffs filed a class action lawsuit against FCA concerning issues related to a number of vehicles using the Pentastar engine from 2014 to 2020. The lawsuit alleges that Chrysler knew about ongoing problems with the valve train, including the rocker arms mentioned earlier.
The Engine suffers from defects in design, manufacturing, and/or workmanship in components of its valve train, specifically the rocker arms, lifters and related components, as well as in the Engine Control Module (ECM) software controlling the timing and function of the lifters, which cause those components to prematurely fail so that they do not adequately and timely transfer the motion of the cam lobes to open and close the valves (the “Defect”).
Page 2; Maugain et al. v. FCA US LLC
While the lawsuit has not yet been settled, the lawsuit also alleges that any fixes – such as replacing the rocker arms – are only a temporary solution that doesn’t solve the underlying issue. The courts aren’t fast, but keep an eye out for further updates on this case.
How Long Does a Jeep 3.6 Engine Last?
If you can maintain it well, a Jeep 3.6 engine should last as long as 200,000 miles which means it can go on for 15+ years. Make sure you replace worn parts like timing chains, brake lines, and suspension regularly to make the engine last longer.
Who Is The Producer of the 3.6 Pentastar Engine?
The 3.6 Pentastar engine is manufactured by Stellantis North America. Chrysler is the former name of the company which was branded into Stellantis North America later.
Is Every 3.6 Pentastar Engine The Same?
No, every vehicle of the three Chrysler models comes with a little bit of diversity. They have individual transmissions and other systems that bring different torque, fuel economy, and horsepower.
Is the Chrysler 3.6L Pentastar a Good Engine?
The 3.6L Pentastar has had a fair number of complaints over the years, but it’s also been in millions of vehicles. It’s definitely not a perfect engine, and the question of whether or not FCA hid the full extent of known problems is worrisome. Intentionally seeking out a Pentastar would be going too far, but plenty of vehicles with the engine are serviceable daily drivers and workhorses.
We’re done talking about the most common Jeep 3.6 engine problems and how you can get rid of them. Hopefully, you already recognized the engine issues you’ve been facing.
Make sure you maintain the engine regularly such as ensuring zero blockage in the passages or coolant contamination, etc. Keep a spare amount of water in the car trunk so you can add it to the overheating engine whenever needed. Good luck with the journey!