As early as the late 1970s, Volkswagen began to think about replacing their rear-engined Type 2 vans with a more modern, front-engined, water-cooled design, as they had very successfully done with their passenger cars earlier in that decade. The reason why in 1980 they still introduced the new rear-engined T3/Vanagon instead is unclear; the front-engined van was delayed until 1990.
The T4, released in 1990, was the first Transporter without a rear engine. This front-wheel drive model was available in two wheelbases, and being front-engined allowed a far greater diversity for special bodies - from wreckers to three-axled minibuses to large box-bodied ambulances, almost everything was possible. Transversely mounted engines with four, five and six cylinders, and especially the very popular TDI diesel engines with direct injection, brought the Transporter's performance back to state of the art, which couldn't really be said about either the T2 or T3.