Introduced in 1990, the T4 was the first in line of Volkswagen Transporters to have a front-mounted, water-cooled engine.   Prompted by the success of similar moves with their passenger cars, Volkswagen had toyed in the late 1970s with the idea of replacing their air-cooled, rear-engined Type 2 vans with a front-engined, water-cooled design.   The reasons for deciding in 1980 to instead introduce a new rear-engined Type 2 (T3)/Vanagon are unclear.    Thus, the introduction of a front-engined layout was delayed until the arrival of the T4.   Although its predecessors are also referred to casually as Transporters, the T4 is the first Volkswagen van to officially use the 'Transporter' title.   After a production run of nearly 14 years, T4 production ceased in 2003, making it second only to the T1 for length of production in its home market.

The T4 was produced in 5 basic body types: Panel Van (without any windows behind the b-pillar), Kombi Van or Half-Panel (with windows between the b and c-pillars), Caravelle/Multivan (with windows all round), Westfalia (a VW-produced campervan) and the Doka — either a single or double cab with a pick-up style platform behind it — Doka deriving from German: Doppelkabine.   They were two standard wheelbases available; "short" (2920mm) and "long" (3320mm) and a variety of different roof heights, including a pop-top roof for campers.

There was one major facelift to the T4, in 1994, when a re-shaped, longer front end was introduced.   This was needed to fit the six-cylinder VR6 engine into the T4's engine bay.   Initially, only Caravelles and Multivans were available with the longer nose, since these were the only models available with the VR6 engine.    The commercial variants continued to be produced with the shorter nose until 1999.    However, campers and other specialist vehicles produced between 1994 and 1999 may have either the short or the long nose, depending on which model was used as the base vehicle.   In keeping with the Type 2's naming convention, the long and short-nose versions are also informally known as T4a and T4b, respectively.

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