LONDON/HOUSTON, July 27 (Reuters) - At least four crude and refined products traders, including two senior managers, have departed Motiva Trading, created under Aramco's Houston refining firm Motiva Enterprises, sources said, amid its merger with Aramco Trading.

Georganne Hodges, executive vice president of supply, trading and logistics, as well as Patrick Reilly, vice president of crude, feedstocks and clean products supply and trading, have left Motiva, according to the sources.

Senior crude trader John Lomax and Matt Ross, trading manager for fuel oil and feedstocks, have also departed the company, the sources added.

The changes come as Saudi Aramco is merging its two energy trading units with Aramco Trading Co (ATC) absorbing Motiva Trading ahead of a potential initial public offering of the business.

In a first step in the company's plan to merge, Motiva Trading changed its name to Aramco Trading Americas.

Saudi Aramco referred Reuters to Motiva for comment. Motiva did not immediately comment. Hodges, Reilly, Lomax and Ross did not immediately respond to requests for comment.

Motiva Trading trades crude oil, feedstocks, refined products and bio-fuels, managing transactions covering 2.8 million barrels per day, according to its website. It was part of Motiva Enterprises, which also owns the largest refinery in the United States. (Reporting by Arathy Somasekhar in Houston and Julia Payne in London; Editing by Kirsten Donovan)