Q: I have a 4×4 pickup and recently had the front and rear differential fluid changed. What could be causing fluid to leak from a hose that is attached to the differential?
A: Differentials have vent hoses. One end of the hose is attached to the differential, while the other end is attached to the truck’s frame. The differential was most likely overfilled. Look for the fill plug on the differential. Get an oil drain pan and remove the fill plug. Oil should only be filled to the bottom of the fill hole. If excess oil starts to come out, let it drain until the fluid gets to the bottom of the hole. Refer to a service manual for specific filler plug locations.