 McAllister struggled to force his way into the first-team, and was loaned to fellow Conference National club Gravesend & Northfleet on 14 December, debuting four days later in a 1–0 defeat away to Hereford United.He went on to score his first goal for Gravesend & Northfleet after just two minutes in a 1–1 draw away to Crawley Town on 26 December, and this was followed up with a goal in the following match, a 2–2 draw at home to Accrington Stanley.McAllister completed the loan spell with two goals from five appearances, before rejoining his former club Eastleigh on loan until the end of 2004–05.