CJ Engines

QUESTION: I just got a 1975 CJ-5, however, the VIN is 1974. It’s supposed to have a 401 in it, and the VIN says 304. how do i tell if it is a 304 or a 401? Thanks, Jess. By the way…it is freekin’ cool!

ANSWER: First off, Jess you didn’t send your e-mail with your message so we couldn’t respond directly. Anyway, CJ’s never came factory with anything larger than a 304 so the VIN is correct. It’s possible to exchange engines though and sometimes Jeep dealers would offer special models with alternate engines in which the VIN wouldn’t reflect. Identifying the engine – on the side of the engine block near the motor mount is typically an engine size marker cast into the block. The numbers are on both sides and pretty big. That will tell you for sure.