Black and Asian production workers at Dagenham claim they were refused transfers to jobs as pounds 30,000-a-year lorry drivers because the selection system was biased against them.
One already held a Heavy Goods Vehicle licence and two others qualified shortly after they were refused a job.
The Transport and General Workers' Union is backing the "Dagenham Seven" in industrial tribunal cases against Ford.
The company is highly sensitive about the ethnic make-up of the 300-strong truck-fleet workforce, based at the Essex plant, and will claim in the tribunals next month that there was no discrimination in the case of the seven litigants.
Union lawyers will argue that the company has presided over institutionalised racism. It is alleged that the selection process has often meant that the highly sought-after jobs are passed from father to son. The drivers earn twice as much as their colleagues on the production lines.
The union's pursuit of the cases has caused bitter internal division at the T&G because shop stewards in the truck fleet argue that selection is based on merit.
Between 40 and 45 per cent of the manual workforce at Dagenham is of ethnic minority origin, but only around 2 per cent of the truck fleet.
In 1990, when the seven were refused lorry drivers' jobs, only three out of 29 successful applicants were from ethnic minorities. Some 143 white workers applied and 53 non-white. It is understood that all 16 drivers recruited last summer were white.
The union will also allege that some of truck-fleet supervisors responsible for selection made racist comments at an equal opportunities course that the company had arranged.
Union officials believe the company has not reviewed the recruitment method because the truck fleet is probably the most powerful section of workers at Ford. The lorries take parts to plants all over western Europe. Because component stocks are always kept to a minimum, a strike in the truck fleet would bring Ford's European operation to a standstill within days.
Bill Morris, general secretary of the T&G, said the union would prefer to settle the issue through negotiation. "Equality is an industrial relations issue which you cannot deal with through the courts. The company should meet the union to discuss proper equal opportunities practices and stop hiding behind paper policies."
Yesterday, the company maintained its policy of refusing to discuss the issue.
Earlier this year Ford was at the centre of a row over an "ethnicly cleansed" photograph. Black and Asian workers were invited to pose with white colleagues to show the racial mix at Dagenham, but when they saw the promotional literature the black and brown faces were replaced by white ones.
The workers concerned each received pounds 1,500 compensation for "hurt feelings". An advertising agency had decided to change the picture for use in Poland because the population there was overwhelmingly white. The amended photograph appeared in Britain by mistake.