//first use 1 texture
car.setTexture("car_1");
//after a while, use 2 to blending
int id = TextureManager.getInstance().getTextureID("car_1");
int id2 = TextureManager.getInstance().getTextureID("car_2");
TextureInfo info = new TextureInfo(id);
info.add(id2, TextureInfo.MODE_MODULATE);
car.setTexture(info);