How many gallons of oil does a 59 cummins take?
A 1959 Cummins engine is not a 5.9L. Assuming you mean a 5.9L 12-valve Cummins (1989-1998), it typically takes **12 US quarts (3 gallons)** of engine oil with a filter change. Always verify with your owner's manual for the exact capacity and recommended oil type.