Reports suggest that the veteran forward could head for the Goodison Park exit at the end of the season after finding regular first-team football hard to come by under Sam Allardyce.
Speaking to talkSPORT, Gray said that bringing Rooney to Rangers would send out a powerful message to the whole of Scottish football.
"If Wayne's time is up at Everton, there's no reason why Rangers shouldn't put their name forward," he said.
"Steven is an attraction. He wants to get it right at Rangers and what a massive signing that would be.
"Wayne Rooney coming to Rangers - that would send out a message to the whole of the Scottish league."