The minivan also offered another change from the large van or the station wagon: front wheel drive, usually found only on smaller automobiles. This made for easier assembly of the vehicle, and allowed for more cargo/passenger area along the floor with the absence of the drive shaft hump. Minivans typically have removable seats and with the seats removed, the cargo area in the larger minivans can hold a 4'x8' sheet of drywall or plywood flat.
In order for the style of minivan to circumvent the current 1980s emission standards, the minivan had to be classified as a truck and could not have four doors like a car. The first minivans were three door configurations with a sliding curbside door.
These early minivans came with four cylinder motors, which although they had better gas mileage, were not able to meet the life span of bigger enginess. It was common to require major engine repairs on the four cylinder motors. Later six cylinder motors were offered and have become a standard choice by purchasers who plan to operate the vehicle for many years. Minivans are also notorious for have problems with their transaxles.
Modern minivans are now very similar to station wagons except they have a higher profile. Many later models added a sliding door on the driver's side.