Ou want to get an oil change every 4,000 miles. how many oil changes do you get in a year driving 1000 miles a month?

3.

1000 miles per month.
12 months in a year.
1000 × 12 = 12000 miles per year

Oil change every 4000 miles.
12000 ÷ 4000 = 3

Therefore 3 oil changes per year.