Cleaning out the cellar rarely pays off like this.

A classic Mercedes-Benz race car has been sold for the second-highest price ever paid for an automobile at an auction.

The 1954 W 196 R Stromlinienwagen crossed the block at an RM Sotheby’s event held at Mercedes-Benz museum in Stuttgart, Germany. When the bidding was done, the winner was on the hook for €51,155,000, or roughly $53 million. Not bad for a car that was once given away.

The W 196 R was one of 14 like it that were built as open-wheel Formula 1 race cars, but the rules back then allowed for full bodywork that was beneficial on high-speed tracks like Monza, which incorporated a 2.6-mile oval. Stromlinienwagen is German for “Streamlined car” and was the name used for it when in this configuration.

The auction car was campaigned across the 1954 and 1955 seasons and driven by Juan Manuel Fangio and Sterling Moss during its career. Mr. Fangio is a five-time Formula 1 champion who is still considered by many racing fans to be the greatest driver in history, while Mr. Moss is often named the best who never won a title.

The car, chassis number 00009/54, is one of four that finished the 1955 season with the Stromlinienwagen body intact, but it would never race again. Following the devastating crash of one of its other cars into a grandstand during the 24 Hours of Le Mans that left 84 dead, Mercedes-Benz withdrew from official competition in all motorsports until 1985.

The W 196 R was retained for the Mercedes-Benz museum collection, but in 1965 was donated to the Indianapolis Motor Speedway museum in time to celebrate the 50th anniversary of Ralph DePalma’s 1915 Indianapolis 500 victory in a Mercedes-Benz.

Since then, the car has spent most of its life as part of the museum’s private access Basement Collection, rather than on the main floor, and has only been brought out on occasion for special events.

The museum is currently undergoing a renovation that is scheduled to be completed before this year’s Indy 500 and it has taken the opportunity to auction several of its vehicles, the W 196 R being by far the most valuable.

“The funds raised from these auctions will be placed in an endowment to care for and grow our collection, adding vehicles and artifacts directly related to our mission, which is to celebrate and preserve the history behind the Indianapolis Motor Speedway and the Indianapolis 500,” the museum told the New York Sun in a statement.

“We are excited that this endowment will provide the museum with long-term financial sustainability, preserving our future for years to come.”

RM Sotheby’s will be auctioning another of the museum’s noteworthy cars that never actually raced on the Indianapolis Motor Speedway oval in Miami in late February, and it has something of a connection to the Mercedes-Benz.

The Spirit of America Sonic 1 driven by Craig Breedlove was the first car to break the 600 mph barrier at the Bonneville Salt Flats in Utah in 1965, the same year the W 196 R came to the United States.

Despite its significance, the jet-propelled car, which is very much a streamliner in its own right, is estimated to sell for only $500,000 to $1 million.

As for the all-time auction record, that also belongs to a Mercedes-Benz.

The 300 SLR “Uhlenhaut-Coupé” was one of two identical cars that were being developed for the ill-fated 1956 racing season under the guidance of engineer Rudolf Uhlenhaut.

Both were preserved by the automaker, but in 2022 it auctioned one at a secret RM Sotheby’s event Stuttgart museum to raise money for the Mercedes-Benz Fund, which supports science and engineering education related to automobiles.

Word got out about the sale and, a few days later, Mercedes-Benz confirmed that the car was sold for an astonishing $143 million. The buyer’s name remains confidential to this day and the car hasn’t been seen in public since.