The oil pump is located on the bottom of the engine. Drain the oil from the oil pan. Remove the oil pan. Remove the oil pump retaining bolts. Reverse the process to install your new oil pump.
In the oil pan
the oil pump sits on the nose of the crankshaft, behind the timing belt sprocket.
Depending on the engine: (According to Haynes Repair Manual) 3.0L - the oil pump is located in the oil pan. You'll have to remove the oil pan, then the oil pump mounting bolt. Lower and remove the oil pump assembly (the oil pump intermediate shaft will come down with the pump). 3.8L - The oil pump is mounted in the oil pump cover/oil filter adapter. The oil pump intermediate shaft is mounted to the timing chain by a clip (I have a 3.0L, so I haven't seen this). You'll have to remove the oil filter, then the oil cooler assembly. Remove the oil pump/oil filter adapter from the front cover (inspect the oil pump gear pocket). Remove the oil pan, the pickup tube bracket nut, and two mounting bolts to remove the oil pump pickup, then lower and remove the pickup. This is probably more info than you wanted, but there you go.
its located at the front of the engine just under the alternator
Cummins (OEM) 12 valve (single wire) oil pressure sensor is located below the injection pump and could be in front of or behind injection pump support bracket. The location was determined by the factory installing the engine. Cummins (OEM) 24 valve (three wire) oil pressure sensor is located below the ECM.
It is in the oil pan.
On top of the oil filter housing
12 quarts
it is around 23.7 quarts of oil. using diesel oil only. 15-40 cummins or rotella oil, check it after running engine.
12 quarts 15w40
Head gasket & oil cooler
Any 15W40 diesel-rated oil is fine.
Head gasket & oil cooler
Yes
15w40
No.No.