The Geo Metro was one of the first American micro cars, and its main focus was a low buy-in cost and high fuel economy. Under its hood was a base 1.0-liter, three-cylinder engine that put down just 55 horsepower, or an optional 1.3-liter four-cylinder with 70 horsepower. Both engines used the same type of oil and had the same oil capacity.
In temperatures below 60 degrees F, Geo recommended using 5W-30 engine oil, but that if temperatures never fall below 0 degrees F, you could use 10W-40 or 10W-30 in its place. For temperatures 30 degrees F or higher, Geo stated that 20W-50 or 20W-40 is also acceptable. Both engines hold a total of 3.7 quarts of oil, including the oil filter.
