Models: 2006-2009 9/7X with V8
Some customers may complain of low oil pressure, no oil pressure, and/or engine noise as well as a possible P0521, which may be the result of a sticking oil pump pressure relief valve. In some instances, this may occur intermittently if the valve frees up when the engine cools down.
If using the service information, diagnose low mechanical oil pressure at the oil filter housing and oil pressure sensor. If low pressure is found, replace the oil pump and flush the oil cooler lines. Clean the inside of the oil pan, change the oil and filter, and re-evaluate the concern. If an engine noise is noticed after replacing the oil pump, follow the service information diagnosis and repair the engine as necessary.