GM Y platform

The Y platform, or Y body, designation has been used twice by the General Motors Corporation to describe a series of vehicles all built on the same basic body and sharing many parts and characteristics. The first was for a group of entry-level compacts including the conventional front-engine compacts built by GM divisions Buick, Oldsmobile and Pontiac from 1961 to 1963. The second, and current, incarnation is used for a high-end rear-wheel drive automobile platform from the 1980s through the 2000s.

The original Y bodies were:

Initially, each of the Y-body compacts from Buick, Olds and Pontiac were only offered as four-door sedans and station wagons when introduced in the fall of 1960 as 1961 models. In mid-1961, each of three divisions introduced two-door pillared coupes to the line with sportier versions of the Buick and Olds models added including the Special Skylark and F-85 Cutlass, both of which featured bucket seats, custom interior and exterior trim, and more powerful engines. For 1962, convertibles were added to the lineup by each of the divisions, with Pontiac also adding the sportier Tempest LeMans coupe and convertible to its compact lineup.

This all-new platform replaced vehicles GM was importing from Europe, selling the Vauxhall Victor that was made in England.

The rear-engined 1960-69 Chevrolet Corvair Z-body up to 1964 used a variation of the rear swing-axle suspension and a transaxle similar to that found on the 1961-63 Pontiac Tempest. The 1961-62 Corvair station wagons even shared the same roofline as the 1961-63 Y-body wagons. Chevrolet's front-engine compact, introduced as the Chevy II for 1962 had some dimensions similar to the Y-body cars, but had a two-inch shorter wheelbase and was also shorter in length and width, its own X-body platform which featured unit-body construction, single-leaf rear suspension and conventional in-line four- and six-cylinder engines.

The Y-body family of cars contained more innovative features than all other American products of that decade. Each model contained at least one notable advance:

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