345 Hemi in the Dodge Charger: Engine Specs, Maintenance, and What Owners Should Know

The phrase "345 Hemi Charger" refers to the 5.7-liter Hemi V8 engine — displacement of 345 cubic inches — found in various Dodge Charger configurations. It's one of the most recognizable V8s in modern American muscle, and understanding how it works, what it needs, and what can go wrong is essential for anyone who owns or is considering owning one.

What Is the 345 Hemi Engine?

The 5.7-liter Hemi (internally referenced as the Eagle engine, often called the "345" for its cubic inch displacement) is a pushrod V8 developed by Chrysler and introduced in 2003. In Dodge Charger applications, it has been the entry-level V8 option, slotting below the 6.4-liter 392 Hemi and the supercharged 6.2-liter Hellcat/Redeye variants.

Key design features include:

• Hemispherical combustion chambers — the defining trait of the Hemi name, which improves airflow and combustion efficiency
• Displacement: 345 cubic inches / 5.7 liters
• Valvetrain: Overhead valve (OHV), two valves per cylinder, operated by pushrods
• Rated output: Approximately 370–375 horsepower and 395 lb-ft of torque in most Charger applications (output varies slightly by model year and tune)
• Fuel Management (MDS): Most versions include Multi-Displacement System, which deactivates four cylinders under light load to improve highway fuel economy

The engine is paired with various automatic transmissions across model years, including the 5-speed automatic in earlier generations and the 8-speed TorqueFlite automatic in later Chargers.

Where the 345 Hemi Fits in the Charger Lineup

The Dodge Charger R/T has historically been the primary 5.7 Hemi trim, though the engine has appeared across several configurations. Understanding the trim context matters for maintenance and parts:

Knowing which engine you have matters when ordering parts, searching TSBs, or describing symptoms to a mechanic — don't assume "Hemi" alone is sufficient.

Common Maintenance Intervals for the 5.7 Hemi

The 5.7 Hemi is a durable engine when maintained properly. That said, it has known characteristics and service needs that owners should understand.

Routine service items:

• Engine oil: Chrysler specifies 0W-40 or 5W-20 depending on model year and climate — always confirm with your owner's manual. Oil change intervals vary; many modern Chargers use an oil life monitoring system rather than a fixed mileage interval
• Spark plugs: The 5.7 Hemi uses 16 spark plugs (two per cylinder), which surprises some owners. Replacement intervals are typically around 30,000 miles for standard plugs, longer for iridium — but this varies by driving conditions and year
• Air filter, fuel filter, and throttle body service follow standard intervals
• Coolant flush: Generally every 5 years or per the manufacturer's schedule

⚙️ The dual-plug design means spark plug replacement costs more labor than a typical V8 — factor this into ownership budgeting.

Known Issues and Areas to Watch

The 5.7 Hemi has a strong reputation for longevity, but there are documented patterns worth knowing:

Multi-Displacement System (MDS) concerns: Some owners report lifter failures associated with the MDS system, particularly on higher-mileage engines. When a lifter collapses or fails, it can cause a ticking or tapping noise, misfires on deactivated cylinders, and — if left unaddressed — more serious internal damage. MDS-related lifter failure is one of the most discussed issues in 5.7 Hemi ownership communities.

Cam and lifter wear: The pushrod design means the camshaft and lifters are inside the block and under oil pressure. Extended oil change intervals or low oil levels accelerate wear in these components.

Exhaust manifold bolts: Some Charger owners encounter broken exhaust manifold bolts, which produce a ticking sound at startup that diminishes when the engine warms up.

Spark plug fouling: With 16 plugs in the mix, one fouled plug is easy to miss without a scan. A misfire code (P030X) can sometimes trace back to a single plug rather than an injector or coil.

Oil consumption: Some 5.7 Hemi engines consume modest amounts of oil between changes. Monitoring oil level between intervals is a reasonable habit.

Diagnosing Symptoms vs. Confirming a Problem

🔧 Common symptoms — ticking, misfires, rough idle, decreased fuel economy — can come from multiple sources on this engine. An OBD-II scan is a starting point, not a diagnosis. A ticking noise might be a collapsed lifter, an exhaust manifold leak, or low oil pressure. The same symptom can carry very different repair costs and urgency levels.

Repair costs for 5.7 Hemi issues vary widely depending on:

• Geographic region and local labor rates
• Model year (early 2000s vs. later generation parts availability differs)
• Whether MDS is present (some owners have MDS-delete kits installed)
• Shop type — dealership vs. independent vs. DIY
• A lifter replacement job, for example, can range from a few hundred dollars in parts for a DIY-capable owner to several thousand dollars at a dealership, depending on how far the damage has progressed

What Shapes Your Outcome as an Owner

The 5.7 Hemi Charger is a well-understood platform with a large aftermarket, extensive owner knowledge base, and long production run. That works in your favor. But outcomes — in terms of repair costs, reliability, and how long the engine lasts — depend heavily on:

• Maintenance history of the specific vehicle
• Model year, since Chrysler made changes to the MDS system, tuning, and transmission pairings across generations
• How the car was driven (highway miles are kinder to this engine than short-trip, stop-and-go use)
• Whether prior owners used the correct oil specification
• Your willingness and ability to handle minor diagnostics or service yourself

A well-maintained 5.7 Hemi Charger with documented service history is a different ownership proposition than one with unknown maintenance gaps — even if both show the same mileage on the odometer.