* Engine size: The Alero came with different engine options (2.2L or 2.4L). The larger engine generally gets worse gas mileage.
* Fuel tank size: The tank size might vary slightly depending on the trim level, but it's generally around 14-15 gallons.
* Driving conditions: City driving yields significantly lower fuel economy than highway driving. Aggressive acceleration and heavy use of air conditioning also reduce mileage.
* Vehicle condition: Properly maintained vehicles tend to get better gas mileage than those in need of repair.
Therefore, there's no single definitive answer. However, based on EPA estimates and owner reports, you could expect a range of approximately 280-350 miles on a full tank under mixed driving conditions. Highway driving could stretch that range a bit higher, while city driving would likely reduce it.
To get a more precise estimate for *your* specific Alero, you'd need to consult your owner's manual or check your fuel economy over several fill-ups to calculate an average.