In case you need car brands and their models just go to autoscout24.de and use this gist.

getCarBrands.js

var brands = [];
$('#make1 option').each(function() { 
	var id = $(this).val();
	var name = $(this).text();
	
	var obj = {
		id: id, 
		name: name,
		models: []
	};
	
	if(typeof navMakeModelData['m' + id] !== 'undefined') {
		var models = navMakeModelData['m' + id].c;
		
		for(var i = 0; i < models.length; i++) {
			if(typeof navMakeModelData[models[i]] === 'undefined') {
				continue;
			}
			var modelName = navMakeModelData[models[i]].t;
			obj.models.push({id: models[i], name: modelName});
		}
	}
	
	brands.push(obj);
});
console.log(JSON.stringify(brands));