The Brentford defender will stay with Rovers until the end of May.
Pirates manager Dave Penney believes McCracken brings a wealth of experience to his side.
"Dave has shown his qualities in the few games he has played for us," he told the club's official website.
"His leadership and communication skills will be an asset to use and I am delighted that he will be with us until the end of the season."
Meanwhile, Harry Pell has joined Hereford on loan until March and Jack McKenna has extended his loan spell at Chippenham Town for another month.