Aramco had 2 DC4s, replaced by 3 DC6s, so I wonder if your recollection of a trio is the latter (also given the comment above).
DC4 10456. N711A. Ex American AL 1947, their only secondhand one. Sold 1956, to ONA, thence Air Algerie and in Cambodia, where it was lost in the 1970s war.
DC4 43094. N1625. New 1947. Sold 1952 to California Eastern, then to Korean Air Lines 1953-67, who finally scrapped it.
DC6B 43559. N708A. New 1952. Sold 1961 to Transair Sweden, with whom it crashed within days at Ndola N Rhodesia, killing Dag Hammerskjold among others.
DC6B 43560. N709A. Also new 1952 and sold 1961 to Transair Sweden, and other European operators, ending up in Peru, scrapped late 1970s.
DC6A 45059. N710A. New 1956. Sold 1960 to Lacsa and on to various others around Latin America. Scrapped 1990.
The complete DC4-6-7 detail is here in a downloadable spreadsheet, just search for "Aramco".
http://www.planelist.net/dc-4.zip
Someone will be along soon I'm sure to relate the bland tail numbers to the aircraft names.