No rub, no harm, no foul.

You may, however, have a slightly worn or misaligned center bearing mount or worn trans output shaft bushing. Try wiggling the front flange on the driveshaft. A leak there is generally conclusive for rear trans seal but may also be bushing replacement.

The worn center bearing may be put off for awhile by lowering or raising the center bearing mount...there's even a volvo bulletin on it. Upshot is add washers either between the bearing mount and the bracket (to raise the mount) or between the bracket and the body (to lower the mount). Since I had installed the IPD lowering springs I chose to raise the mount about 4mm (two washers) during a local Washington Volvo Club (shameless plug...y'all come out to Marten's now!) DIY. Works a lot better, but I know I'm going to have to replace that bearing mount if not the bearing in a couple years (90 740T 107K w/Dawes Device, rrfpr, bare right rear tire....)