5.7 Hemi v8 engine has been one of the most popular engines known for its power and efficiency. With a horsepower of 485 and 475 lb-ft of torque, the popularity of this gasoline engine is not something to be skeptical about. The 5.7 Hemi has been a strong and reliable choice for the masses since its release in 2003.
Just like with any machine, the 5.7 Hemi also has its issues and drawbacks.
What is a 5.7 Hemi Engine?
5.7 Hemi was named after the hemispherical shape of the combustion chamber in this engine. Without getting into mechanical details, the geometry of rounded combustion chambers and dome-shaped cylinders are much more fuel-efficient than their flat counterparts due to the less surface area. With the old age concept mixed with advanced technologies, the 5.7 Hemi was able to produce much more power and torque with less fuel burned. The valves of the Hemi are placed on the opposite sides of the head to increase valve size and airflow.
The Merits of 5.7 Hemi:
The 5.7 Hemi is an excellent engine. Reliability and sturdiness have earned 5.7 Hemi its reputation. The 5.7 Hemi is:
– More Powerful than engines with flat designs having the same displacement and fuel economy.
– The 5.7 Hemi engine design is as robust as it gets. The durability and reliability are well sought after.
– The cool factor, that comes with a powerful ride is also not something to overlook.
There’s a compelling reason that 5.7 Hemi has powered more than one flagship car in its influential lifetime of 20 years, including Jeep, Dodge, and Chrysler. 5.7 Hemi is a trustworthy engine that people appreciate. Problems do occur with every high-performance engine in long run. Holding the engines responsible for that is not something we metalheads should do.
How Long Your 5.7 Hemi will last?
If you keep your engine healthy with oil changes and regular maintenance, as the reviews suggest, the Hemi is expected to last more than 300,000 miles. Hemi has taken reviews very seriously throughout the years to refine their engine model and the newer models are expected to last even more. With appropriate care, your Hemi can outlive other car parts easily.
Problem with 5.7 Hemi:
You are likely to find several problems relating to 5.7 Hemi on the internet forums. We’ll discuss the most common issues owners stumble upon with their 5.7 Hemis.
1. The Ticking
Popularly known as the “Hemi Tick”, 5.7 Hemis are likely to develop a ticking sound from the beginning.
The perspective on this issue is different from user to user, some are more inclined to believe that this is a characteristic of the engine’s pushrod design. The pushrod design consists of more moving elements, so being a little noisy is not something to be worried about. The ticking sound is more prominent when the engine is pushed extremely hard.
On the other hand, other users have associated the tick with faulty lifters and valves.
In the end, it’s very difficult to trace back to the definitive explanation of why the ticking occurs, but the problems persist for some users.
2. Breaking of Exhaust Manifold Bolts
Practically every long mileage 5.7 Hemis has this issue with their exhaust manifold bolts – the parts of the manifold that attach to the two cylinders in the rear. Without official explanations, the problem is speculated as a heating issue. The theory suggests, that the two cylinders in the rear are subjected to more heating than the rest because of the lack of cooling, which stresses the bolts to snap.
As an owner of 5.7 Hemi, you should be prepared to change the exhaust manifold bolts eventually after 100,000 miles. If you are experienced enough, you might be able to do it yourself, but for most people, they have to take their Hemi to a service station.
3. The New Multi Displacement System
Modern 5.7 Hemis are furnished with the new multi-displacement system, popularly known as MDS. The MDS turns off four of the cylinders when cruising at a constant speed. The intention with this is to increase fuel economy, which it certainly does.
The problems with MDS are not much widespread as the previous two. Some of the owners love the new technology in their 5.7 Hemis, claiming a smooth transition between deactivation and reactivation.
Others are not much comfortable with the MDS. They allege a buzzing sound when the engine transitions, which is more prominent with an aftermarket exhaust.
But, most of the 5.7 Hemi owners believe that MDS could potentially be bad for engines in long term, considering a part of the engine being turned off and on constantly. As with any new technology, the judgment is still pending on the harmful effects of MDS.
The latest models come with a simple button to disable the system.
4. The Misfires
5.7 Hemis are equipped with 16 spark plugs. Misfires aren’t a common problem with Hemis, but having so many spark plugs can cause occasional misfires due to old and worn-out plugs. Other things like faulty injectors, lifter rollers, and ignition coils can also prompt a misfire.
Keep up the regular maintenance and change oils timely. The problems mentioned here mostly are not frequent occurrences but are surely annoying.
The Bottom Line
Hemi 5.7 engine is a beast in terms of power and reliability, the faults we mentioned in this article are most certainly common for Hemis, but no high-performance engine is perfect in drivability and performance.
The exhaust manifold bolt issue is not a major issue, but a frequent one with Hemi engines, which is a headache to experience more than once or twice in its lifetime. MDS is still in its early days to comment on, but the longevity use may present itself soon.
Chances are, that your Hemi will smoothly run for more than 200,000 miles without giving you any issues. Problems occur due to age and poor maintenance of Hemis, as with any engine. Overall, 5.7 Hemi is reliable, powerful, and fun.