Drive train rattling. Goes away in 4x4. What is it?
I have a 2013 Lincoln Navigator.
It developed a rattle/grind under the driver side towards the front.
It happens at the low end of the gear range when accelerating. Usually only
gears 2 - 5. It seems like it is related to the amount of torque.
It Rattles for a few seconds, there is a clunk, and it's gone.
It only happens in the "2x2" setting.
If I switch to "4x4 Auto" or "4x4" it will not make the noise.
The tranny needed work and was just replaced...that didn't stop the noise.
I have replaced the 4x4 Vacuum actuator in the engine compartment...that
didn't fix the noise.
Any ideas on what this could be?
Transfer case chain rattling? If it is then one of those clunks will become a bang and transfer case parts will be all over the ground.