Last Updated on: 7th September 2023, 12:43 am
Chrysler introduced the third generation Hemi engine family in 2003. The first engine for the 2003 Dodge Ram pickup trucks was this 345 cubic inch 5.7-liter V8 gasoline Hemi.
The 5.7L Hemi engine replaced the 5.9-liter V8 LA/Magnum engine (code name Eagle).
Over the next several years, the 345 Hemi engine was offered in a range of Chrysler cars, including the Dodge Durango, Chrysler 300C, Dodge Magnum R/T, Jeep Grand Cherokee, Dodge Charger, and others.
Let’s look at the design of the Chrysler 5.7L 345 Hemi engine, as well as the engine’s typical difficulties, reliability, and durability.
Design of the Chrysler 5.7L 345 Hemi Engine
The 5.7-liter engine was completely rebuilt from the ground up.
The 345 Hemi engine features a cast-iron cylinder block with a deep skirt and a 90-degree angle between cylinder banks, similar to the 4.7L PowerTech V8.
Four bolts per main bearing support the cast nodular iron crankshaft. It features skirt-coated lightweight aluminium pistons and powdered metal connecting forged rods.
Up to 2008, pistons used wider rings, measuring 1.50/1.50/3.0 mm. After the 2009 redesign, pistons were provided with thin piston rings – 1.20/1.20/2.0 mm ring pack.
The chain-driven camshaft is located between the cylinder banks.
The timing chain is comparably long because the camshaft is purposely elevated to minimise the length of the pushers (lighter parts mean less inertia).
The 5.7 Hemi engine has aluminium cross-flow cylinder heads with two valves and two spark plugs per cylinder.
The HEMI-shaped chambers now have a flatter shape on both sides with squish shelves, which improves efficiency and reduces emissions.
The camshaft controls the intake and exhaust valves using pushrods and rocker arms. The engine also has beehive valve springs and roller-style hydraulic lifters.
The 5.7 Hemi has MDS, a cylinder deactivation technology that reduces fuel consumption and pollutants (Multi-Displacement System).
This method turns off the fuel in four cylinders (two in each bank) and keeps the intake and exhaust valves closed by controlling the flow of oil through the lifters of corresponding valves.
- The diameter of the intake valves is 2.00 inches (50.8 mm)
- The diameter of the exhaust valves is 1.55 inches (39.4 mm)
The intake manifold is made of plastic. There is also an electronic throttle body (drive-by-wire).
In 2009, Chrysler launched the new 5.7L Hemi (Eagle 5.7) The efficiency and stability of this huge engine have been greatly improved.
The incorporation of three more oil channels and a larger front cam bearing in the block to support variable valve timing was the most important alteration (VVT).
The refurbished engine block features a new, very durable crankshaft, which, by the way, is still composed of cast iron (a 53021300BB casting).
New pistons, a dual-mass crankshaft damper, stronger connecting rods, and a new dual-mass crankshaft damper are all available to accommodate the smaller ring pack.
Beginning July 2009, certain models incorporate an electrically controlled, variable length intake runner (the active intake). Cylinder heads have undergone significant evolution.
The new intake ports are 14% larger and almost square than the original rectangular ones, with a 14% increase in airflow.
The D-shaped exhaust vents have a higher ceiling. Two millimetres have been added to the intake valves.
Instead of the spherical 85cc chambers with squish shelves seen in the original heads, the revised heads have 65cc oval chambers. The compression ratio was increased to 10.5:1.
Following the phase-out of the 4.7-liter V8 PowerTech engine in 2013, the 5.7-liter Hemi became the standard V8 engine.
Chrysler 5.7L 345 Hemi Engine Specs
- 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
- Configuration: V
- 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
- 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) or 6 months
- Applications: Chrysler 300C SRT-8, Dodge Magnum SRT-8, Dodge Charger SRT-8, Jeep Grand Cherokee SRT-8, Dodge Challenger SRT-8
Reliability & Issues of the Chrysler 5.7L 345 Hemi
Let’s talk about the Chrysler 5.7 Hemi engine. With general, there are no serious design flaws in the third-generation Hemi V8s, and the 5.7 Hemi is a reliable, dependable, and sturdy engine.
If it hadn’t been accessible, Chrysler would not have used it on some of their most famous automobiles and trucks for over 20 years.
In the real world, however, nothing is perfect, and there is no such thing as an ideal engine that does not break.
The most common 5.7 Hemi issues and difficulties are mentioned below.
Ticking issues with the 5.7L HEMI
Valve springs dropping/cracking in early Hemi engines was a well-known problem. In 2007, Chrysler corrected the problem by replacing the springs.
Some owners are reporting a strange ticking sound coming from the valvetrain in the current 5.7L Hemi engine as of today.
From 2009 forward, “the hemi tick” is common on Hemi V8s equipped with the MDS system. The calm ticking, on the other hand, is completely natural and undisturbed.
If the sound becomes more clear and contains metallic tones, it’s time to be worried.
This might indicate seized lifter rollers or failing lifters. In addition to ticking, this condition may be accompanied by a misfire and the check engine light.
If you leave this alone for too long, you’ll almost surely end up with a destroyed camshaft and a lot of metal shavings in the oil.
It’s also worth noting that the MDS (cylinder deactivation system) is quite sensitive to oil conditions. Stick to the prescribed oil change schedule and only use the approved oil to avoid problems.
Spark plug longevity and misfires
Manufacturer-supplied spark plugs aren’t particularly long-lasting. They should be changed every 30,000 to 40,000 miles on the Chrysler 5.7 Hemi.
Dealing with an ignition-related misfire in a Hemi V8 may be a hassle since each cylinder has two spark plugs.
It will also triple the amount of maintenance necessary, and a pack of 16 current spark plugs isn’t cheap.
Broken exhaust manifold bolts
The most common problem with the 5.7L HEMI is broken exhaust manifold nuts. This problem has been brought up by a few owners on many times.
The bolt on the rear passenger manifold is frequently the first to break.
Some speculate that this is due to the fact that this is the engine’s hottest part. The exhaust manifold, like the brake bolts, bends and warps.
Is the Hemi 5.7L Engine Reliable?
It’s not the best, but it’s a lot better than the least dependable engines. Problems will develop at some point throughout the engine’s lifetime, especially if it has recorded a large number of kilometres (150-200k).
Overall, the 5.7L Hemi is a great engine that is both long-lasting and fun to drive.
A well-maintained 5.7 Hemi engine has a range of 250,000 to 300,000 miles. Unfortunately, even well-maintained HEMIs may create significant problems for some people.
