Cadillac Commercial Chassis

The Cadillac Commercial Chassis was basically a strengthened version of the long-wheelbase Cadillac Series 355 frame and the Series 75 was intended to carry the extra weight of the bodywork, rear deck and cargo area of funeral coaches and ambulances. Specifically designed for professional car use, it used the GM D platform, and the rear of the Cadillac Commercial Chassis was considerably lower than the passenger car frame, thereby lowering the rear deck height as well for ease of loading and unloading. As shipped from the factory to custom coachbuilders for final assembly, Cadillac's Commercial Chassis typically consisted of the front end sheetmetal with all lighting and trim, dashboard, air conditioning (if specified) and the main road controls. Rear quarter panels and sometimes the front door shells were shipped with the chassis for use in the finished coachwork.

Federal Motor Vehicle Safety Standards in the United States and Canada calling for increased weight ratings as of the 1979 model year spelled the end of automobile-based ambulances and the beginning of the van and truck-based units seen today throughout North America.

Cadillac's adoption of unibody construction after 1996 means that Cadillac-based funeral coaches are usually produced from modified sedans. Cadillac supplies incomplete "kits" of its XTS sedans (and DTS/DeVille until 2011) to Master Coachbuilders which are certified for conversions and assembly of finished funeral vehicles.

Load carrying duties are now shared with the Cadillac Escalade, based on the Chevrolet Suburban.

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