In the early 1980s, Mawu and Naawu spread to all parts of the country. They typically established a presence in a new area by focussing on a large or influential factory where news of struggle spread to neighbouring factories and communities. Often, after these unions targeted a factory, a dispute erupted; the industrial action then served to raise the profile of unionisation in general and in these unions in particular; a cadre of new leaders then emerged who set out to recruit in neighbouring workplaces; once a sufficient number of workplaces were organised, they launched a new branch. In this way the metal unions pioneered expansion for themselves and other Fosatu unions.

Auto expansion

Before the 1980s, the auto industry was based mainly in the Eastern Cape and was dominated by large assembly plants. In 1985, these plants contributed 71 per cent of Naawu's paid-up membership. Largely dependent on auto assembly were the smaller tyre and rubber, and auto component sub-sectors. Tyre and rubber logically fell into auto components but it always remained more strongly linked to the assemblers sector.

Auto was smaller than other sectors in Numsa, in particular engineering. On Numsa's formation it had 24 000 members compared to motor's 40 000 and engineering's 70 000. Yet it occupied a strategic position in the Eastern Cape and national economy which enabled these workers to wield considerable power in the metal sector.

In the early 1980s, Numarwosa/UAW began to expand into other centres, particularly the northern Transvaal, where manufacturers such as Toyota, Sigma and BMW had moved in a cost-cutting exercise. Previously, auto assemblers had set up plants next to Port Elizabeth's working harbour where parts were shipped in; now the ‘just in time’ production system pioneered by the Japanese eliminated the use of warehouses to store excess supplies. This meant that components were flown directly to plants when required and it thus became possible for assemblers to relocate factories from harbour cities to the major markets of the Transvaal. Component manufacturers followed suit.