You may need to put a light coat of RTV on the outer edge of the seal, with the divot in the surface it may be just enough to leak. You also might want to polish the axle surface where the seal rides, it may have a slight burr or be worn from the seal riding on it for years. I once used a ready sleeve on an axle to repair where the seal had ridden, the trick was finding one the would fit. It took the aid the machine shop to locate the proper diameter sleeve (Ford 390 harmonic balancer in that case).
A good Tech Tip
