My car has an oil leak and transfer case leak.
Hi. The transfer case leak is a very common issue with these vehicles, especially at high mileage. The problem occurs when the pump for the transfer case begins rubbing against the side of the case. Over time, it will drill through the side wall of the case and allow oil to start leaking out. Usually, there is a clip that holds the pump from rubbing against the side, however, these are prone to break and then the pump is free to move around. This should be fixed as soon as possible because if you let the case leak, it will cause internal damage and you will need a whole new case. If there isn’t too much damage, GMC has a revised clip for sale that will fix the issue. A certified technician, such as one from YourMechanic, would be able to help you find the source of the oil leak. This should also be taken care of soon as running the engine low on oil can cause significant damage.