2014 Limited ecoboost 212,000 miles
I am getting a drivetrain bearing whine from under the car. Its speed related not load related. Sometimes I hear it in the back, sometimes i hear it just behind the front seats, sometimes it sounds like its coming from the front passenger side. Not a wheel bearing. Was thinking the driveshaft carrier bearings, but wanted to see if any one experienced this noise and it being the Viscous Coupler on the rear diff?
I drained and replaced the rear diff fluid and made no difference. Seems to be worse when it gets below 25*F outside. Didnt hear it at all when the temp was in the mid 30's, temp dipped and the noise came back. Ill be putting it up on stands probably this weekend but I have to drive it to my shop to bull inside, so that being said I might not hear it once its inside the building.
Also suspecting the PTU. I changed the fluid twice since 100,000 miles with royal purple but I just sucked the old fluid out. Once I get it on stands, Im going to drill and tap a drain plug. that being said, has anyone drained the old fluid and added a cleaning agent to the case and let it idle in gear briefly to try and clean out some of the goopy stuff? Fill with lube run at idle drain then fill again?
I am getting a drivetrain bearing whine from under the car. Its speed related not load related. Sometimes I hear it in the back, sometimes i hear it just behind the front seats, sometimes it sounds like its coming from the front passenger side. Not a wheel bearing. Was thinking the driveshaft carrier bearings, but wanted to see if any one experienced this noise and it being the Viscous Coupler on the rear diff?
I drained and replaced the rear diff fluid and made no difference. Seems to be worse when it gets below 25*F outside. Didnt hear it at all when the temp was in the mid 30's, temp dipped and the noise came back. Ill be putting it up on stands probably this weekend but I have to drive it to my shop to bull inside, so that being said I might not hear it once its inside the building.
Also suspecting the PTU. I changed the fluid twice since 100,000 miles with royal purple but I just sucked the old fluid out. Once I get it on stands, Im going to drill and tap a drain plug. that being said, has anyone drained the old fluid and added a cleaning agent to the case and let it idle in gear briefly to try and clean out some of the goopy stuff? Fill with lube run at idle drain then fill again?