Since 2005, Chrysler’s 300 has been offered with six different engine options, from a problematic 2.7L V6 to a 470 HP Hemi V8. We review their specs, reliability, and problems.
The Chrysler 300 has only been around for two generations, with the first starting in 2005, and the second still going strong today. One thing the 300 has always offered is a diverse lineup of engine options, which, depending on the generation, ranged from a mostly problematic 2.7L V6 to a massive 6.4L V8 built for speed.
Note that the engine lineup in the Chrysler 300 has changed since the car’s initial release, so a 2005 model year won’t have the same engine options as a 2015. With that in mind, which Chrysler 300 engine is right for you? To answer that, you’ll first need to learn a little about each, as performance and economy vary greatly–and none are without fault. We review the pros and cons of the different Chrysler engines, including specs, fuel economy, and problems.
Chrysler 300 Engine Options
2.7L V6 Engine
When the 300 was released, it came in five trims. The base trim came with the Chrysler LH 2.7L V6 engine that was good for 200 horsepower. It was an adequate offering for bargain shoppers with dual overhead cams, aluminum block and heads, and cast iron pistons.
The main issue with this engine was an oil sludge problem that was due to lower oil capacity that led to higher engine temps. This resulted in poor conditions for the oil, causing it to gel up in the oil pan. As a result, a lot of these engines failed catastrophically.
Dodge-focused YouTuber “Marspeed” has produced a video overview that covers the 2.7L V6’s oil sludge issue.
“The build-up of oil sludge was a very common issue with this engine,” he explains in the clip. “This is when the oil gets very thick–like a gel-type substance–and it reduces the flow of oil through the engine, causing excess wear or a failure.”
Despite these issues, the 2.7L V6 did deliver decent fuel economy numbers, sporting an EPA-rated 26 miles per gallon at highway speeds. Chrysler replaced the 2.7L with a more powerful 3.6L Pentastar V6 for the 2011 model year, which we’ll cover later.
3.5L V6 Engine
The 3.5L single overhead cam V6 was pushing 50 more horsepower than the previous trim’s 2.7L V6, for a total of 250 horses. It boasted 17 miles per gallon when about town and 25 miles per gallon on the highways. This engine was around from 1993 until the 2011 model year, when it was replaced by the 3.6L Pentastar V6, a long run for any engine.
Unfortunately, this engine was the same design as the previously mentioned 2.7L as well, and it faced similar oil sludge engine problems. Similar to the 2.7L, the oil sludge issue could be prevented by changing the engine oil every 3,000 miles.
3.6L V6 Pentastar Engine
The Pentastar V6 is one of the most technologically advanced engines produced by Chrysler. It’s also wildly successful and appears in many more vehicles other than the Chrysler 300. The V6 replaced the 2.7L and 3.5L V6s, offering 292 horsepower. This engine is 38% more powerful, consumes 11% less fuel, and is 42 pounds lighter than its 3.5L predecessor.
However, the new 3.6L did have a few of its own issues quirks. One issue is that the cylinder heads produced a ticking sound, which was followed by misfires in the neighboring cylinders and ultimately power loss. Chrysler ultimately learned from these issues quickly and fixed the recurring problem for future production vehicles using this engine.
Additionally, some Pentastar engines experience rocker arm failures which also are identified by ticking, though it isn’t the same as the cylinder head issue. Despite all these issues, the Pentastar V6 is highly reliable with proper maintenance and there are even examples of 600,000 miles on one engine.
5.7L Hemi V8 Engine
The 5.7L V8 Hemi is a pushrod engine with a cam-in-block overhead-valve design. It’s a monster that has applications that date back to World War II.
In the 300, this engine was initially capable of 340 horsepower, increasing in 2009 to 360 horsepower. Not only was this engine powerful, but it was sophisticated as well. The Multi-Displacement System (MDS) allows the large V8 to deactivate up to half of its cylinders to save fuel.
Thanks to tech like MDS, even the 5.7L Hemi squeezes out 16 mpg while driving around town, and up to 25 mpg at highway speeds, which isn’t bad for a V8.
Common problems from the Hemi range from engine ticking to lifter problems with the MDS. The diagnoses for the engine ticking are as serious as faulty lifters, a seized lifter roller, or broken exhaust manifold bolts. That’s right, the engine gets pretty hot around the exhaust manifold, and apparently, the manifold can warp, putting strain on the bolts that hold it to the engine.
Eventually, the bolts break causing a metal-on-metal ticking sound. This was the cheapest of the problems we found in our research.
6.1L & 6.4L Hemi V8 Engines
The SRT nomenclature stands for “Street and Racing Technology” and it couldn’t be more true. In the SRT-8, the 6.1L V8 Hemi rests under the hood. This engine is a revised 5.7L block cranking out a whopping 425 horsepower. The engine also has a forged crankshaft, stronger connecting rods, and a cast aluminum intake manifold for higher rpms.
If you needed any more convincing about this engine’s goal, Chrysler didn’t employ the MDS technology we were discussing in the previous trim. Fuel savings and emissions weren’t really on the radar when designing this engine.
Speaking of, you’d be spending more time at the gas pumps in this car, with its measly 13 miles per gallon in the city and 19 miles per gallon on the highway. Bearing in mind that these numbers are the best the car can do, they’re probably a bit worse.
The woes of this engine bear a resemblance to the 5.7’s problems, ranging from seized lifter rollers to cylinder misfires and oil consumption. Despite such, this engine is lauded as dependable.
The SRT-8 received a new 6.4L V8 from 2012 to 2014 but was phased out as a trim after that. The current 2021 Chrysler 300 is offered in just two engines: 3.6L V6 Pentastar and the 5.7L Hemi V8, which both featured the new TorqueFlite eight-speed automatic transmission.
Which Chrysler 300 Engine is Best?
While you can likely find a first-generation model with the 2.7L or 3.5L V6s for a few thousand dollars, they’re not as reliable as the Pentastar that replaced them. If you do go with a first-gen 300, just avoid the 2.7L V6 altogether.
We recommend a 3.5L with the lowest mileage possible, and even then be sure to have it inspected by a Mopar mechanic before purchasing.
As for second-gen 300s, anything after 2011 will have the Pentastar 3.6L V6 as its base engine, so we suggest starting there. For a small increase in price without sacrificing too many miles per gallon, the 5.7L V8 is also a reliable option to consider.
If you want to turn things up to 11 and make your neighbors angry, the 6.1L V8 or the short-lived 6.4L V8 are the engines for you, though prices on these are going to be higher around $30k.
Photos: Stellantis
