Updated: Feb 2
✔ This article has been fact checked.
In 2003, Chrysler unveiled the third generation of Hemi engines. A 345 cubic inch, 5.7L V8 gasoline Hemi engine producing 425 hp and 569 nm torque, it was the first engine for the 2003 Dodge Ram pickup trucks.
The 5.9L V8 LA/Magnum engine (code named Eagle) was replaced by the 5.7-liter Hemi engine.
The 345 Hemi engine was offered in a variety of Chrysler vehicles throughout the following few years, including the Dodge Durango, Chrysler 300C, Dodge Magnum R/T, Jeep Grand Cherokee, Dodge Charger, and others.
Table of Contents:
Chrysler 5.7L 345 Hemi Engine Design
Similar to the 4.7L PowerTech V8, the 345 Hemi engine has a cast-iron cylinder block with a deep skirt and a 90-degree angle between cylinder banks.
The cast nodular iron crankshaft is supported by four bolts per main bearing. It has powdered metal connecting forged rods and pistons made of lightweight aluminium with a skirt coating.
Pistons used wider rings, measuring 1.50/1.50/3.0 mm, up to 2008. Pistons were given thin piston rings, a 1.20/1.20/2.0 mm ring set, after the 2009 revision.
Between the cylinder banks is the chain-driven camshaft. The camshaft is intentionally elevated to reduce the length of the pushers and reduce inertia, which results in a rather lengthy timing chain.
This engine features aluminium cross-flow cylinder heads with two valves and two spark plugs per cylinder. The HEMI-shaped chambers now have squish shelves and a flatter form on both sides, which boosts efficiency and lowers emissions.
Pushrods and rocker arms are used by the camshaft to operate the intake and exhaust valves. Beehive valve springs and hydraulic lifters in the roller form are also used.
With MDS (Multi-Displacement System), a cylinder deactivation technology, the 5.7 Hemi uses less fuel and emits less pollutants.
With this MDS technology, the intake and exhaust valves are kept closed while the fuel is turned off in four cylinders (two in each bank). This is done by regulating the oil flow through the corresponding valve lifters.
The exhaust valves have a 1.55-inch (39.4 mm) diameter, while the intake valves are 2.00 inches (50.8 mm) in diameter. Plastic is used to make the intake manifold. A drive-by-wire electronic throttle body is also included.
Chrysler introduced the brand-new 5.7L Hemi engine (Eagle 5.7) in 2009. The engines stability and efficiency have been dramatically improved.
The most significant modification was the addition of three more oil channels and a bigger front cam bearing in the block to accommodate variable valve timing (VVT).
The rebuilt engine block has a new, extremely robust crankshaft that is still made of cast iron.
To fit the smaller ring pack, new pistons, a dual-mass crankshaft damper, stronger connecting rods, and a new dual-mass crankshaft damper are all included.
Some versions, starting in July 2009, include an electronically controlled, variable length intake runner (the active intake).
The development of the cylinder heads has been significant. The original rectangular intake ports have been replaced with 14% bigger, almost square ones that have a 14% higher airflow.
The ceiling is taller above the D-shaped exhaust vents.
The intake valves have been extended by two millimetres.
The updated heads contain 65cc oval chambers rather than the spherical 85cc chambers with squish shelves seen in the original heads.
The compression ratio was raised to 10.5:1.
The 5.7L Hemi engine replaced the 4.7-liter V8 PowerTech engine in 2013 as the default V8 engine.
Manufacturer: Chrysler, Saltillo Engine plant in Ramos Arizpe, Mexico
Production years: 2005-2010
Cylinder block material: Cast iron
Cylinder head material: Aluminium
Fuel type: Gasoline
Fuel system: Sequential multi-port fuel injection
Number of cylinders: 8
Valves per cylinder: 2
Valvetrain layout: OHV
Bore: 103.0 mm (4.06 in)
Stroke: 90.9 mm (3.58 in)
Displacement: 6,059 cc (370 cu in)
Type: Four-stroke, naturally aspirated
Compression Ratio: 10.3:1, 10.5:1 (2009+)
Power: 425 hp (318 kW) at 6,000 rpm
Torque: 420 ft-lb (569 Nm) at 4,800 rpm
Firing order: 1-8-4-3-6-5-7-2
Engine oil weight: SAE 0W-40
Engine oil capacity: 6.6 litres (7.0 qt) with oil filter
Oil change interval: 6,000 miles (10,000 km) / 6 months
Applications: Chrysler 300C SRT-8, Dodge Magnum SRT-8, Dodge Charger SRT-8, Jeep Grand Cherokee SRT-8, Dodge Challenger SRT-8
Problems & Reliability
In general, the third-generation Hemi V8s have no significant design problems, and the 5.7L Hemi is a reliable engine. Chrysler would not have used it on some of their most well-known cars and trucks for more than 20 years if it hadn't been reliable
However, in the actual world, nothing is perfect, and a faultless engine that never malfunctions does not exist.
1. Ticking Sound
A well-known issue with early Hemi engines was the valve springs dropping or snapping. Chrysler replaced the springs in 2007 to fix the issue. The latest 5.7L Hemi engine has a weird ticking sound that some owners notice originating from the valvetrain.
From 2009 onward, Hemi V8s with the MDS system are frequently seen with "the Hemi tick". The calm ticking is completely normal, if the sound becomes more clear and contains metallic tones, it's time to be worried.
This might be a sign of seized lifter rollers or worn-out lifters. This problem may be accompanied by ticking as well as a misfire and the check engine light. You'll almost certainly end up with a damaged camshaft and a lot of metal shavings in the oil if you wait too long to take action.
It's also important to keep in mind how sensitive the MDS (cylinder deactivation system) is to oil conditions. To prevent issues, follow the recommended oil change schedule and only use Chrysler recommended oil.
2. Spark Plugs & Misfires
Spark plugs that are provided by the manufacturer aren't especially durable. For the Chrysler 5.7 Hemi, these should be replaced every 30,000 to 40,000 miles.
A Hemi V8 may be difficult to fix an ignition-related misfire since there are two spark plugs for each cylinder. Additionally, it will need three times as much maintenance, and a pack of 16 spark plugs is not cheap.
3. Broken Exhaust Manifold Bolts
This is the most frequent issue with the 5.7L Hemi engine. Usually, the first bolt to break is the one on the rear passenger manifold. Some speculate that this is because this is the hotter area of the engine, causing it to bend and warp.
Is the 5.7L V8 Hemi Reliable?
Although it has some issues, it is still far more reliable than some engines. Throughout the engine's lifespan, issues are likely to occur at some point, especially if it has covered a lot of miles (150-200,000).
The 5.7L Hemi is a great engine all around that is durable and pleasant to drive.
A 5.7L V8 Hemi engine may last between 250,000 and 300,000 miles with proper maintenance. Unfortunately, some people may experience serious issues even with well-maintained Hemi engines.
Below are images of the Chrysler 5.7L Hemi engine.