1984 Buick Century specs & fuel economy
The 1984 Buick Century is rated 25 MPG combined by the EPA (21 city, 31 highway). That is 29% above the 19.4 MPG average across the 217 EPA configurations in the 1984 Midsize Cars class, placing it in the 97th percentile of its class. At 12,000 miles at $3.50/US gallon it costs about $1,680 a year to run.
EPA data snapshot imported 2026-09-06 · United States · US gallons
The 1984 Buick Century has 9 EPA-listed configurations in our 2026-09-06 data snapshot. Listed transmissions: Automatic 3-spd; Automatic 4-spd. Compare the engine, drive type and fuel ratings below before matching an individual car by VIN.
How the 1984 Buick Century compares in its class
EPA publishes each configuration on its own. Ranking one against every configuration EPA rated in the same class and model year is our calculation from the 2026-09-06 snapshot, not an EPA figure.
- Combined rating
- 25 MPG
- 1984 Midsize Cars average
- 19.4 MPG
- Difference
- 29% above average
- Rank in class
- 97th percentile of 217 configurations
- Reference annual energy cost
- $1,680 · 12,000 miles at $3.50/US gallon
The class average covers every 1984 configuration EPA rated in the Midsize Cars class, compared in MPG only, so electric and liquid-fuel ratings are never mixed. The reference cost is a fixed assumption for comparison; the calculator below takes your own mileage and prices.
Engine, transmission and fuel economy
All 9 1984 Century configurations EPA rated, each linked to its source record. Combined primary-fuel ratings: 18 to 25 MPG. Missing values remain “Not reported.”
| Engine / transmission / drive | Primary fuel | City | Highway | Combined | Source |
|---|---|---|---|---|---|
| 2.5L 4-cyl · Automatic 3-spdEPA engine descriptor: (FFS) | Regular Gasoline | 20 MPG | 28 MPG | 23 MPG | EPA #26935 |
| 3L 6-cyl · Automatic 3-spdEPA engine descriptor: (FFS) | Regular Gasoline | 17 MPG | 24 MPG | 20 MPG | EPA #26936 |
| 3.8L 6-cyl · Automatic 4-spdEPA engine descriptor: (CAL,FFS) | Regular Gasoline | 16 MPG | 23 MPG | 19 MPG | EPA #26937 |
| 4.3L 6-cyl · Automatic 3-spdEPA engine descriptor: (DIESEL) | Diesel | 21 MPG | 31 MPG | 25 MPG | EPA #26938 |
| 2.5L 4-cyl · Automatic 3-spdEPA engine descriptor: (FFS) CA model | Regular Gasoline | 20 MPG | 28 MPG | 23 MPG | EPA #28003 |
| 3L 6-cyl · Automatic 3-spdEPA engine descriptor: (FFS) CA model | Regular Gasoline | 16 MPG | 22 MPG | 18 MPG | EPA #28004 |
| 3.8L 6-cyl · Automatic 4-spdEPA engine descriptor: (FFS) CA model | Regular Gasoline | 16 MPG | 23 MPG | 19 MPG | EPA #28005 |
| 4.3L 6-cyl · Automatic 3-spdEPA engine descriptor: (DIESEL) CA model | Diesel | 21 MPG | 29 MPG | 24 MPG | EPA #28006 |
| 4.3L 6-cyl · Automatic 4-spdEPA engine descriptor: (DIESEL) CA model | Diesel | 21 MPG | 31 MPG | 24 MPG | EPA #28007 |
What would it cost you to run?
Enter your own mileage and prices — these are assumptions, not live pump prices.
| Configuration | Annual cost | Calculation basis |
|---|---|---|
| 2.5L 4-cyl · Automatic 3-spdEPA #26935 | $1,826 | Regular Gasoline operation |
| 3L 6-cyl · Automatic 3-spdEPA #26936 | $2,100 | Regular Gasoline operation |
| 3.8L 6-cyl · Automatic 4-spdEPA #26937 | $2,211 | Regular Gasoline operation |
| 4.3L 6-cyl · Automatic 3-spdEPA #26938 | $1,680 | Diesel operation |
| 2.5L 4-cyl · Automatic 3-spdEPA #28003 | $1,826 | Regular Gasoline operation |
| 3L 6-cyl · Automatic 3-spdEPA #28004 | $2,333 | Regular Gasoline operation |
| 3.8L 6-cyl · Automatic 4-spdEPA #28005 | $2,211 | Regular Gasoline operation |
| 4.3L 6-cyl · Automatic 3-spdEPA #28006 | $1,750 | Diesel operation |
| 4.3L 6-cyl · Automatic 4-spdEPA #28007 | $1,750 | Diesel operation |
Miles ÷ combined MPG × price per gallon; electric versions use miles ÷ 100 × kWh/100 miles × price per kWh. Plug-in hybrids show gasoline operation only. Maintenance, insurance and depreciation are excluded.
Enter your VIN. Check the car before you buy.
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No subscription. No charge to check the VIN. Report contents vary by vehicle; applicable tax is shown at checkout.
See what the paid report includes →Use these specs to check a 1984 Century listing
- Confirm the seller’s car is a 1984 Buick Century and which of the 2 listed transmissions it has.
- Check that it takes Regular Gasoline or Diesel on the vehicle’s own fuel label.
- Run the VIN for identity, title and reported history — none of which is in this EPA data.
- Check open recalls on the NHTSA lookup and have the car inspected.
Compare nearby model years
These links match the EPA model name. They do not establish that parts or equipment are interchangeable between years.
Sources reviewed
Open the underlying public source and verify that its scope matches the question you are asking.
Frequently asked questions
What is the gas mileage of the 1984 Buick Century?
The 1984 Buick Century is rated 25 MPG combined by the EPA (21 city, 31 highway). That is 29% above the 19.4 MPG average across the 217 EPA configurations in the 1984 Midsize Cars class, placing it in the 97th percentile of its class. At 12,000 miles at $3.50/US gallon it costs about $1,680 a year to run.
What transmission does the 1984 Buick Century have?
EPA records list Automatic 3-spd; Automatic 4-spd across the 9 rated configurations of the 1984 Buick Century. These are model-level configurations. Match the individual car’s VIN and factory build information before identifying a replacement transmission.
What fuel does the 1984 Buick Century use?
The 1984 Buick Century is listed with Regular Gasoline, Diesel. Match the particular configuration and follow the vehicle’s fuel label and owner’s manual.
How much does the 1984 Buick Century cost to run per year?
About $1,680 in fuel or energy at 12,000 miles at $3.50/US gallon, using the 25 MPG combined EPA rating. That excludes maintenance, insurance, depreciation and charging-session fees. Enter your own mileage and prices in the calculator on this page for a figure that matches your driving.
Are these the exact specifications of my Century?
These are the 9 EPA model-year configurations recorded for the 1984 Buick Century, not a decode of an individual VIN or a complete trim catalogue. Confirm identity, installed equipment and service requirements with the car’s VIN and manufacturer records.
Will I achieve the listed fuel economy?
EPA ratings support comparisons under standardized test conditions. Your result depends on driving, weather, tyres, load, charging pattern and vehicle condition. The cost calculator uses the listed combined rating and your entered prices.