Most engine oil pumps will last a very long time as in 70,000 to 150,000 miles or even more.
To keep your engines oil pump working properly make sure you change the engine oil every 3,000 to 5,000 miles and change the engine oil filter along with it.
Engine oil pump failures are usually caused by lack of engine oil changes or running the engine low on oil.
The oil pump needs to have good clean oil to flow through the engine oil pump and to keep the engine running properly and smoothly to keep the parts lubricated.
The oil flows through the engine oil pump and through the crankshaft through holes to lubricate the main bearings as well as the rod bearings and then lubricates the camshaft and lifters as well.
When the oil pump doesn't have clean oil or a good oil level to pickup the oil out of the pan then the oil pump can starve for oil and then the gears in the oil pump can wear down.
That then leads to loss of engine oil pressure.
The oil pump is the heart of the engine so you need a properly working engine oil pump to keep the engine running smooth for a very long time.