In the 1984 Dodge D150, miles-per-gallon varies by engine and configuration. Rough figures: inline-6 models around 18–22 mpg on the highway, and V8 variants typically 15–18 mpg combined; real-world results depend on transmission, gearing, payload, and driving conditions.
Overview of the 1984 D150 lineup
The 1984 D-series pickups offered multiple powertrains and configurations, including the 225 cubic inch Slant-6 inline-six and V8 options such as the 318 (5.2 L) and 360 (5.9 L). Buyers could choose 2WD or 4x4 drivetrains and manual or automatic transmissions. Rear-end gearing and payload weight were also major drivers of fuel economy, so there isn’t a single universal mpg figure for all D150s from that year.
Estimated MPG by engine and drivetrain
Note: The following ranges reflect common configurations from the era; actual mileage varies with maintenance, payload, tire size, and driving style.
- Slant-6 225 cu in (3.7 L) — 2WD with manual transmission: highway about 20–23 mpg; with automatic: approximately 18–21 mpg. City driving often in the mid-teens; combined roughly 18–21 mpg.
- 318 cu in (5.2 L) V8 — 2WD (manual or automatic): highway roughly 16–20 mpg; combined around 14–17 mpg; city typically 12–15 mpg. Automatic trans tends to be on the lower end of this range.
- 360 cu in (5.9 L) V8 — 2WD: highway around 15–18 mpg; combined about 13–16 mpg; city typically 12–14 mpg. 4x4 versions usually dip a bit further.
- 4x4 variants — Generally 1–3 mpg lower than their 2WD counterparts, depending on transfer case and gearing.
These figures reflect era-typical conditions and mechanical setups. Individual trucks can deviate based on maintenance history, carburetor/tuel delivery condition, altitude, and how heavily they’re loaded.
Factors that affect fuel economy
Several factors beyond engine choice determine real-world mpg for a 1984 D150. Key considerations include payload (hitch weight and cargo), tire size and condition, transmission type, rear-axle gearing, overall vehicle weight, and driving style. Classic carbureted engines also respond to tune and fuel quality, which can noticeably impact efficiency.
To maximize efficiency within the constraints of a vintage pickup, owners emphasize regular maintenance, proper carburetor adjustment, correct spark timing, and keeping tires properly inflated and aligned.
Summary
The 1984 Dodge D150 does not have a single MPG figure; it spans a range depending on engine and configuration. Inline-6 models typically deliver higher highway mileage (roughly 18–22 mpg), while V8 variants tend to fall into the mid-teens for mixed driving (roughly 15–18 mpg). Real-world numbers depend on drivetrain (2WD vs 4x4), transmission, gearing, payload, and upkeep. For a specific truck, consider its engine, transmission, and rear-end gear as the primary factors shaping fuel economy.