For 1937 the Kadett was offered as a small and unpretentious[2] two door "Limousine" (saloon) or, at the same list price of 2,100 ℛ︁ℳ︁, as a soft top "Cabrio-Limousine".

The 1,074 cc side-valve engine came from the 1935 Opel P4 and came with the same listed maximum power output of 23 PS (17 kW) at 3,400 rpm.

The General Motors version, which had been further developed by Opel's North American parent, was intended to provide a soft ride, but there was some criticism that handling and road-holding were compromised, especially when the system was applied to small lightweight cars such as the Kadett.

Mechanically and in terms of published performance there was little to differentiate the two, but the "Spezial" had a chrome stripe below the window line and extra external body trim in other areas such as on the front grill.

The "Kadett KJ38" was intended to fill the market segment of the Opel P4, but the KJ38, priced at 1,800 ℛ︁ℳ︁, was more expensive than the P4 and its reduced specification left it with the image of a car for poor people (..Image des Arme-Leute-Autos..) at a time when economic growth in Germany was finally fostering a less minimalist approach to car buying.

Faced with a wide range of German "small litrage" models to choose from, Soviet planners wanted a car that closely followed the general type of the KIM — a 4-door saloon with an all-metal body and 4-stroke engine.

They, therefore, rejected both the rear-engined, two-door KdF-Wagen (future VW Beetle) and the two-stroke powered, front-wheel-drive, wooden-bodied DKW F8, built by the Auto Union Chemnitz plant in the Soviet occupation zone.

The Rüsselsheim plant had been deeply involved in the Nazi war effort, producing aircraft engines for the Luftwaffe, and consequently has been heavily damaged by the Allied air raids.

This project was conducted by design bureaus formed as Soviet-German joint ventures under the Soviet Military Administration in Germany (SMAD).

The two-seat Opel GT was heavily based on Kadett B components, its body made by a French contractor, Brissonneau & Lotz, at their Creil factory.

[17] In November 1979, the car went on sale in the United Kingdom, some five months before the Vauxhall Astra Mark 1, the British version, was launched in March 1980.

Technologically, the Kadett D was part of a major investment for Opel (and General Motors as a whole) in a new front-wheel drive architecture, with an all-new family of engines and transmissions which would later be applied in the larger Ascona C and the smaller Corsa A in 1981, and 1982, respectively.

A carry-over 1196 cc Opel OHV engine from previous generations of the Kadett producing 55 PS (40 kW) and a top speed of 140 km/h (87 mph) was also offered on entry-level models from launch.

In the United Kingdom, Opels and Vauxhalls were initially sold through separate marketing operations, with overlapping lineups that competed directly with each other.

By 1982 this anomaly had been sorted out and the Opel lineup was limited to the well-equipped five-door Berlina (1.3S or 1.6S) and the sporty 1.6 SR, leaving most of the market to the Vauxhall-badged cars.

This was an estate car with rustic trim, fitted with a limited-slip differential, reinforced suspension and more suitable tires, increased ground clearance, a skid plate, and shortened front fenders.

Garmak Motor was also reproduced Kadett D after 1984 in Jakarta, only for local market general buyers and taxi fleets until around 1995.

The Kadett E (sold as the Vauxhall Astra Mark 2 in the United Kingdom) was introduced in August 1984, and was voted the 1985 European Car of the Year.

[25][26] The 1984 model was also developed into a more conventional three-box design with a boot (trunk), badged as the Vauxhall Belmont in the United Kingdom, launched at Frankfurt 1985.

There was also a van version with a raised roof, called the Opel Kadett Combo in Europe, and the Bedford Astramax in the United Kingdom.