The used Nissan Altima engine most frequently replaced is the 2.5L QR25DE four-cylinder, though the 3.5L VQ35DE V6 is also commonly available. The QR25DE has a documented excessive oil consumption problem that can lead to rod bearing failure when ignored. This chain-driven unit features a cast-iron block and aluminum cylinder head. Buyers should inspect for milky oil residue, which in... https://moonautoparts.com/engines/nissan/altima