Actually, in a sense there are 3 generations of the body. I say this because in 98 they changed the car cosmetically, and we think of that as the beginning of the 2nd generation. But in 2000 they made several changes to the engine/trans, body styling and chassis/suspension. See:1fastaltima said:the 1st gen altima is U13
the newest sylvia is S15
the newest skyline is R34
the newest Sentra is B15
the 2nd gen alty i would think would be U14. But it could still be U13 as well. It's the exact same car under the body. Nothing changed other than outside.