Minor glitch with my 727....

Ok, I described the cable part wrong.... A few months ago, I made the mistake of telling my friend he could drive it, before he even left the driveway he over shifted the trans in park. He pulled on the shifter so hard, he ripped the tip off the end(the knob that connects to the gear lever on the side of the trans) I re-threaded the end of the cable, and put everything back together.

I was under the false impression that it had a full manual valve body, only reason I've been driving it, and lately it's been having a delay going into drive. So I haven't been driving it at all(maybe once a month, give or take)

But ever since the cable incident happend, there's been the noise when in reverse, it doesn't do it any other time.