Charles Ellicott Commentary 1 Kings 2:39

"And it came to pass at the end of three years, that two of the servants of Shimei ran away unto Achish, son of Maacah, king of Gath. And they told Shimei, saying, Behold, thy servants are in Gath." — 1 Kings 2:39 (ASV)

Achish son of Maachah: In 1 Samuel 27:2, we read of Achish son of Maoch, king of Gath; but chronology makes it most unlikely that the same person should be referred to here. The name may have been hereditary.