The oil drain plug on the 2000 Ford Ranger is on the rear of the oil pan. It is located under the vehicle near the center.
According to the 2000 Ford Ranger owners manual: ( 5W - 30 ) for your 2.5 L four cylinder engine
lorftion drain plags 3.0 l Ford
The 2000 Ford Ranger firing order is 1-3-4-2. The number one cylinder is the one closest to the front.
In a 2000 Ford Ranger : ( the 2.5 liter four cylinder engine , which was the only four cylinder engine offered from the factory for a 2000 Ford Ranger , not like the 2001 model when they started with the 2.3 liter DOHC later that model year )
The oil drain plug is located on the bottom side of the engine of a 2007 Ford Ranger. It is directly on the oil pan.
The proper gap for the 2000 2.5L Ford Ranger is .044"
( 5 W - 30 ) according to the 2000 Ford Ranger owners manual
underneath the engine
According to the 2000 Ford Ranger owners manual the 2.5 liter four cylinder engine takes ( 5W-30 engine oil )
Belt.
I checked motorcraft.com , and the owners manual for a 2000 Ford Ranger and they both indicate that the only 4 cylinder engine in a 2000 Ford Ranger is a 2.5 L. With filter change it takes 4.5 quarts ( 4.3 liters )
Code P0304 on 2000 Ford Ranger is: Misfire at cylinder 4 detected. May be cause by a bad spark plug.