The Volkswagen truck plant here employs more than 20,000 workers, but that's 3,000 too many, reports Sigi Mezner, a sales official with Volkswagenwerk AG. Dr. Carl H. Hahn, chairman of the VW board of management, agrees, saying the factory is 20 percent overstaffed.
Why not cut back on the workforce? ''We can't,'' Hahn replied. ''It's politically impossible at this time.''
Thus, to avoid building a lot of vehicles that can't be sold, the plant is running on short time - reduced workdays, extra days off, and six-week vacations a year. The West German government pays the workers for lost time.
Simply, production workers, who make about $6.50 an hour, are ''paid for 40 hours, but work 35,'' says Mezner.
The Hannover truck plant is part of what the Volkswagen management in the United States calls ''the other Volkswagen,'' the VW that builds many types of vehicles and components, even robots, other than the familiar Rabbit.
''The other Volkswagen,'' for example, is West Germany's second largest truckmaker, after Daimler-Benz, as well as the producer of special-interest vehicles, the water-cooled ''water boxer'' flat engine, industrial engines, and campers.
The Volkswagen Vanagon is built in the Hannover plant.
The factory produces only a few air-cooled engines these days for industrial applications alone - not for automobiles. The air-cooled engine was what put VW on the road map.
The new water-cooled engine, used in the VW Vanagon, gives far higher performance than the air-cooled flat engine it replaces. Horsepower is up 22 percent.
The water boxer engine, in fact, appears to have a big future at Volkswagenwerk AG and may be used in future front-engine passenger cars to lower the front hood and improve the coefficient of drag.
VW also has a deal with MAN, a large West German truck and bus maker, to produce trucks in the Hannover plant. The capacity of the LT series of between 2 .8- and 5-ton gross vehicle weight is 160 units a day in two shifts.
Indeed, VW'a image as a maker of mass-market cars - the venerable beetle and the Rabbit - is far from the whole story of the carmaker which literally rose from the ashes of World War II and in the early days was rejected by some of the major auto manufacturers of the world, including Ford.
Too, some of the cars with a VW emblem on the hood, VW doesn't even build.
Consider the Volkswagen convertible - first the beetle and now the Rabbit - which is produced in the Karmann factory in Osnabruck. The sporty beetle-derived Karmann Ghia of the 1960s and '70s was powered by a VW engine but also built in Osnabruck by Karmann. The Volkswagen Scirocco is a product of Karmann, the 600, 000th of which came off the line May 5.
Then there is the Joker, popular in Western Europe and sold as the VW Campmobile in the US, which is adapted and outfitted by Westfalia Werke in Wiedenbruck and sold in VW dealerships around the world.
As in the United States, the market for commercial vehicles has long been depressed by a slow-moving economy. Now, however, the market seems to be on the rise, according to Dr. Bodo Dencker, manager of the VW truck plant here. The money now being spent on the factory - $75 million a year - is aimed at making the plant competitive when the demand for commercial vehicles hits a more normal stride.
Along with the current Vanagon being built here, VW also will produce a new 4 -wheel-drive Vanagon, developed by Porsche, for 1984. The demand for such vehicles is picking up smartly as more car manufacturers get into the act.
''We expect it to create a new market for the vehicle,'' asserts Dr. Dencker. Also, the factory will produce 4-wheel-drive pickup trucks.
The overstaffing at its truck plant, VW expects, will fade as demand goes up.
Absenteeism runs at 4 to 5 percent, except during sowing time in the spring and harvest time in the fall when it jumps to 12 percent or more.
''Many of the workers live on a farm,'' Mr. Mezner explains.
Significantly, more white-collar workers are unionized than production workers - 98 percent compared with 96 percent.
Workers get a 45-minute lunch break and four 16-minute breaks during the workday. About 19 percent of the assembly-line workers are non-German - Turks, Greeks, Italians, etc. - and 13 percent are women.
The truck plant was built in the mid-1950s to meet the rising demand for VW Transporters as well as provide jobs in the Hannover area, about 50 miles from the main VW operations in Wolfsburg on the East German border.
The factory has been added to since then and now stretches almost as far as the eye can see. The plant, which is being increasingly automated and refined, turns out 800 vehicles a day. VW commercial vehicles are not sold in the United States because of the ''chicken tax,'' Mezner explains, although the tax has not deterred the Japanese.
The ''chicken war'' erupted in 1963 when the US tried to break into the chicken market in Western Europe, but the Dutch and the French said no. In retaliation, the US clamped a 25 percent tax on all commercial vehicles shipped to the US.
''Because of the tax, the vehicles are noncompetitive in the US market,'' concludes Mezner.