The GM Y platform, sometimes referred to as Y body, can refer to very distinct vehicles and automobile vehicle platforms. The first time GM used the Y moniker was in 1961 thru 1963, when the term Y body was used on a series of entry-level compact vehicles from Buick, Pontiac, and Oldsmobile. The second time was in reference to the platform that underpins the Chevrolet Corvette and only briefly, the Cadillac XLR.