The T1 Barndoor

The early versions of the T1 van until 1955 were often called the T1a or "Barndoor", because of the enormous rear engine cover, while the later versions with a slightly modified body (the roofline above the windshield is extended), smaller engine bay, and 15 in (381 mm) wheels instead of the original 16 in (406 mm) ones were called the T1b. From the 1963 model year, when the rear door was made wider (same as on the T2), the vehicle was referred to as the T1c. 1963 also saw the introduction of an optional sliding door for the passenger/cargo area instead of the outwardly hinged doors typical of cargo vans. This change arguably makes the 1963 VW the first true minivan, although the term wouldn't be coined for another three decades.