W126 reverse slipping

[LandYaghtLover]

Fluid looks good and at right level. All forward gears seem fine, to me. No vac leaks that I can tell of. It only in reverse. At first I though it was a brake problem, like a pad catching because that is exactly what it feels like. But I decided to hold it in reverse and just let it idle for a while. There is a "whirling" sound coming form the trans (I think). And the car will catch reverse slowly. Although tonight it jerked hard into reverse with barley any throttle input.

Ideas? I hope I am not loosing reverse, but I am betting its a trans issue. I am VERY new to this car and know little.