Mercedes-Benz continues to lose ground as it grapples with production shortfalls caused by tight semiconductor supplies. First-quarter deliveries tumbled 20 percent to 62,251.
Audi rounded out the top five, reporting sales of 35,505 in the quarter, down 35 percent from a year earlier.
It also helped BMW that it committed early to large quantities of semiconductors to keep production flowing. The automaker is now reinforcing supplies.
According to Cox Automotive data, as of March 21, BMW had a 30-day supply, compared with a 37-day pool for the overall luxury segment.
Smith said he has only a two- to three-day supply on the ground at his BMW stores.
To offset the lack of inventory, dealers are preselling into the pipeline.
Smith said he begins each month with 75 to 85 percent of his allocation already sold.
"Cars don't stay long," he said. "We get a chance to gas it up, clean it up — we're pre-printing all the paperwork."