What the 2008 Dodge Charger SRT8 emits and how much fuel it uses

The 2008 Dodge Charger SRT8 is a full-size performance sedan powered by a 6.1-liter V8 engine that produces 425 horsepower. The EPA rates it at 16 miles per gallon in the city and 25 miles per gallon on the highway, with a combined rating of 19 mpg. This fuel economy reflects the engine's size and performance tuning rather than efficiency optimization.

For emissions, the 2008 Charger SRT8 meets the Tier 2 Bin 8 standard under the Clean Air Act, which was the federal requirement for that model year. This classification means the vehicle produces higher nitrogen oxide (NOx) and particulate matter than smaller, less powerful engines, but still complies with the regulations in effect at the time of manufacture. The vehicle's annual emissions estimate, based on typical driving, is approximately 10.5 tons of CO2 equivalent per year — a figure that varies depending on actual driving patterns and conditions.

Key Takeaways

  • The 2008 Charger SRT8 achieves 16 city / 25 highway / 19 combined mpg according to EPA testing, making it less fuel-efficient than most vehicles on the road.
  • The vehicle meets Tier 2 Bin 8 emissions standards, which allow higher pollution output than smaller engines because of the vehicle's weight and power class.
  • Annual CO2 emissions from this vehicle are roughly 10.5 tons per year under typical driving, though this varies based on how and where you drive.
  • The 6.1-liter V8 engine requires premium gasoline (91 octane or higher) to run properly and avoid engine knock.

Engine specifications and fuel requirements

The 2008 Charger SRT8 uses a naturally aspirated 6.1-liter V8 engine — no turbocharger or supercharger. The engine is tuned for high output rather than efficiency, with a compression ratio of 10.25:1. This high compression ratio is why the vehicle requires premium fuel; regular 87-octane gasoline can cause detonation and reduce power output.

Fuel tank capacity is 18.5 gallons. At the EPA combined rating of 19 mpg, a full tank provides a driving range of approximately 351 miles before empty. Real-world range varies significantly depending on driving style — aggressive acceleration and highway speeds above 65 mph reduce fuel economy noticeably.

How the 2008 model year compares to other Charger generations

The 2008 Charger SRT8 was the first generation of the modern Charger nameplate revival. It was significantly heavier and more powerful than the original 1960s Chargers, weighing 4,360 pounds curb weight. The second-generation SRT8 (2015–2023) used a 6.4-liter V8 and achieved similar fuel economy despite the larger displacement, because of incremental improvements in engine management and transmission efficiency.

Compared to non-SRT8 Chargers of the same year, the SRT8 version consumed more fuel and produced more emissions due to the larger engine and higher performance tuning. A standard 2008 Charger with the 3.5-liter V6 achieved approximately 25 mpg combined, roughly 6 mpg better than the SRT8.

Emissions testing standards and what Tier 2 Bin 8 means

The EPA's Tier 2 emissions program, which was in effect when the 2008 Charger SRT8 was certified, divided vehicles into eight bins based on their NOx output. Bin 8 is the highest-emission bin allowed for passenger vehicles under that standard. Vehicles in Bin 8 produce up to 0.20 grams of NOx per mile, compared to 0.05 grams per mile for Bin 1 vehicles.

The Charger SRT8 was classified in Bin 8 because of its engine size and power output. The EPA allows higher-emission vehicles in higher bins as a trade-off for allowing manufacturers to produce vehicles across a range of sizes and performance levels. A vehicle's bin classification does not mean it is unsafe or illegal — it means it meets the specific standard set for its category at the time of manufacture.

Real-world fuel economy and driving factors

EPA fuel economy ratings are based on standardized laboratory testing, not actual driving. Real-world fuel economy for the 2008 Charger SRT8 typically ranges from 14 to 22 mpg depending on several factors. Aggressive acceleration, frequent hard braking, and driving in stop-and-go traffic reduce efficiency significantly. Highway driving at steady speeds of 55–65 mph yields better economy than the EPA highway rating suggests, while speeds above 70 mph reduce it.

Cold-weather driving also reduces fuel economy because the engine requires a richer fuel mixture to start and warm up. Tire pressure, wheel alignment, and engine maintenance affect efficiency as well. A vehicle with underinflated tires or a dirty air filter will consume more fuel than one properly maintained.

Fuel type and octane rating requirements

The 2008 Charger SRT8 requires 91-octane premium gasoline. Using 87-octane regular gasoline can cause engine knock (detonation), which damages the engine over time and reduces power output. Some drivers report that the vehicle's knock sensor can adjust timing slightly to compensate for lower octane, but this reduces performance and fuel economy further.

Premium gasoline costs more per gallon than regular — the difference varies by region and season, but typically ranges from 30 to 60 cents per gallon. Over a year of driving, this adds several hundred dollars to fuel costs compared to a vehicle that runs on regular fuel. Some fuel retailers offer mid-grade (89-octane) gasoline, which is not recommended for this vehicle and may cause the same knock issues as regular fuel.

Maintenance and emissions system components

The 2008 Charger SRT8 includes a catalytic converter, oxygen sensors, and an evaporative emissions control system to meet Tier 2 Bin 8 standards. The catalytic converter reduces tailpipe emissions of carbon monoxide, hydrocarbons, and NOx. If the check engine light comes on, it often indicates a problem with one of these emissions components.

Replacement catalytic converters for the SRT8 are expensive — typically $800 to $1,500 for an OEM part — because of the vehicle's high-flow design. Aftermarket converters are available at lower cost but may not meet emissions standards in states with emissions testing programs. Regular maintenance, including spark plug replacement every 30,000 miles and fuel filter changes, helps keep the emissions system functioning properly.

Frequently Asked Questions

Can I use regular gasoline in a 2008 Charger SRT8?

Using regular 87-octane gasoline is not recommended and can damage the engine. The SRT8 requires 91-octane premium fuel. Regular fuel may cause engine knock, which reduces power, increases fuel consumption, and can harm internal engine components over time.

What does Tier 2 Bin 8 mean for my vehicle's emissions?

Tier 2 Bin 8 is the highest-emission category allowed for passenger vehicles under the EPA standard that was in effect in 2008. Your vehicle meets that standard, but it produces more NOx and particulates than smaller, less powerful vehicles. This classification reflects the vehicle's size and engine power, not a defect.

How much does it cost to fuel a 2008 Charger SRT8 for a year?

At 19 mpg combined and 12,000 miles per year of typical driving, you would use approximately 632 gallons of premium fuel annually. At current premium prices (which vary by region), this typically costs $2,200 to $2,800 per year, roughly $400 to $600 more than a comparable vehicle running on regular fuel.

Is the 2008 Charger SRT8 street legal in states with emissions testing?

Yes. The vehicle was certified to meet federal emissions standards for 2008 and will pass emissions testing in states that conduct it. However, modifications to the emissions system — such as removing the catalytic converter or disabling emissions controls — make the vehicle illegal and subject to fines.