Is this something that requires immediate attention? I just had the whole real differential replaced a year ago. What needs to actually be done to fix this? There is nothing noticeable when it's driving. How long can it be driven like this.
My car has 185000 miles.
My car has an automatic transmission.
There is a seal that sits in between the two halves of your differential housing which keeps the oil inside of this housing from leaking. The oil inside the differential housing keeps the pinion gears lubricated. It depends on how bad it is leaking in terms of how quickly this will need immediate attention, however, I would not recommend waiting too long as this could cause some serious damage should this seal completely fail and leak all of the oil out. I would recommend having an expert mechanic from YourMechanic come to your home to diagnose and repair the leak for you.