The take-out joint on Adam Clayton Powell Jr. Boulevard, between West 145th and 146th streets, is the last of a chain that opened in 1948 and once had five Harlem locations. It has been on life support since being shuttered in August by the Health Department because violations, and now Grinan fears she may have to close the restaurant for good.
She is trying to get investors to save the historic restaurant. But she faces mounting costs — fines totaling at least $15,000 because of the health violations, back rent and costs needed to upgrade kitchen equipment to get permission from the Health Department to re-open.
"We weren't able to pay the rent, and the landlord said that if I couldn't find an investor, I'd have to give back the place," said Grinan, 55, whose father, Sherman Hibbitt, founded the restaurant.
Hibbitt was known as the "unofficial mayor of Harlem." The walls of the restaurant's five locations were lined with pictures of Hibbitt with everyone from President Harry Truman and First Lady Eleanor Roosevelt to writer and poet Langston Hughes.
"It was exciting going to Sherman's when they had the jukebox and the picture of Mr. Sherman with the presidents hanging on the wall in the 50s," Ronnie Spector, of the famed 60s girl group the Ronettes, told DNAinfo in December. "It made you feel like somebody."
Other notable diners included the Isley Brothers, the Sugar Hill Gang and the late Percy Sutton, who was Malcolm X's lawyer and became the city's highest level elected black official when he was voted Manhattan Borough President in 1966.
The joint's popular pork ribs, pigs feet and spaghetti made with barbecue sauce attracted a loyal following, even during the roughest of times. But now the restaurant has fallen on hard times. Outside, the Sherman's sign is missing letters and reads "Man's Bar B.Q."
"What happened to her is not unusual for establishments that have been in business a long time and managed to survive but weren't able to upgrade and continue marketing," said Lawrence King, small business advisor for the Harlem Business Alliance. "Time catches up with them."
King helped Grinan work out a business plan. He estimated it could take up to $50,000 to get the location up and running again, and he believes a comeback is not out of the question.
"If she is able to pitch her business to the right investor in terms of history and importance to Harlem, like Sylvia's, it remains to be seen," King said.
Despite Grinan's farewell note, saying, "Each and everyone of our customers are special in our hearts," she said she's still meeting with interested investors.
"I'm still getting calls. People want to see me re-open. That's why I haven't given up hope," Grinan said. "I still feel that I'm going to somehow be able to get back started again. It's just taking longer than I expected."