I just picked up my car from a round of TSB service along with a noisy differential. The grind and clutch service went well but the differential noise could not be repaired right away. It seems the differential sprang a leak where one of the shafts exits. It was a small leak but it managed to drain a significant amount of lube over the last 24K possibly resulting in the noises. After refilling the case the noise remains. I have the car to drive while awaiting a new differential. Anyone experienced any leaks like this before?