Tesla's sales slip comes amid a record year for competitor BYD in the ever-important Chinese market.

Tesla has had a special relationship with China allowing it to do things in the country that have been the envy of other U.S. automakers. That connection will be tested if Donald Trump is elected to a second term in the White House and a bigger trade war breaks out.

U.S. automaker Tesla sold 68,280 China-made electric vehicles in October, down 5.3% from a year earlier, data from the China Passenger Car Association (CPCA) showed on Monday. Deliveries of China-made Model 3 and Model Y vehicles fell 22.