German auto giants represent the gold standard in car brands the world over. But sales of BMW, Mercedes and Volkswagen at home are hitting the lowest level since national unification.

Despite the record strength of the euro against the dollar, sales of German cars reached 3.6 million units between January and October, up 11 percent from last year.

"2007 is likely to be the fifth record year in a row for exports," the German automotive federation (VDA) said.

But during the same period, new car registrations in Germany fell eight percent to 2.62 million units while orders were down seven percent.

"2007 may be the worst year for the automobile market in Germany since unification (in 1990) with just 3.1 million new registrations," said Willi Diez, the director of the IFA automobile industry institute in the southwestern town of Gieslingen.

The reasons are varied but the economic mood and global warming are playing a part.

In the last decade, sales of German cars have more than doubled. And unlike the automobile sector in other parts of Europe, German manufacturers have managed to increase their share of the national economy.

But could this year mark the end, or the beginning of the end, of the golden age?

"You've got to take a lot of exceptional factors into account," VDA spokesman Rotter Eckehart said.

Last year's boom — spurred by the impending rise in value-added tax to 19 percent from 16 percent on January 1 — has led demand to sink this year.

"That's 100,000 cars that were bought in 2006 (before the tax hike) that are missing this year," Diez said.

Eckehart said German consumers are also still skittish about the impact of the tax rise, leading them to hold off on major purchases.

"The age of cars driven in Germany has never been this high at more than eight years old," he added.

Eckehart ticked off all the factors that the industry complains about in its home market: high taxes, rising insurance prices, the heady price of gasoline and the debate about global warming.

He noted that this last point is particularly potent in Germany, where climate protection tends to be a higher priority among consumers even as they fret about the prospect of new "green" taxes on fuel.

"The phenomenon has hit the mass-market manufacturers like Volkswagen, Opel and Ford the hardest," Diez said.

"At the high end of the market, buyers have more disposable income anyway."

The European Commission has set a target to reduce carbon emissions of new cars to 120 grams per kilometre by 2012 but Germany, known for its trucks and gas-guzzling all-terrain vehicles, is fighting for a sliding scale based on the category of vehicle.

Meanwhile analysts do not expect the German car sector to brighten much next year.

"The market may see a slight recovery in 2008 thanks to falling unemployment and slightly higher wages," Diez said.

"But sales will remain a bit weak with 3.28 units sold" — well below the German record of 3.8 million units.