Causes of a High Pitched Whining Noise in a Ford Lincoln Navigatorby Jen Davis
The Lincoln Navigator is an upscale model of the Ford Expedition. Vehicle noises in it can be one of the most difficult problems for which to determine the exact cause, because there are several completely different parts that could be making them. The easiest way to narrow your search is to figure out when the the whining noise is occurring and what part is running or operating when the noise begins or increases.
Loose or glazed-over serpentine belts inside the Navigator's engine can cause a squealing or whining noise to emit from the engine compartment. This noise will be amplified when the SUV is first started or if gets wet under the hood. Typically, you can put a vehicle with a squealing belt in neutral and rev up on it several times in order to get the belt to temporarily stop squealing or whining.
Power Steering Pump
A worn-out power steering pump has a tendency to whine when the vehicle is turned hard in one direction or the other. If the whining noise is only occuring when you turn your Navigator, you should have the power steering pump checked out by a mechanic. A low grade whine is often a signal that your power steering pump is low on fluid or beginning to fail.
In some cases, the current generated in the alternator can cause a whining noise to emit. This may be caused by the current not being properly transmitted into the diodes. If the whine begins when you start the Navigator and seems to increase and decrease in correspondence with the rpms the engine is producing, there is a good chance the whine is being caused by the alternator.
If your Lincoln Navigator has a turbocharger, the whine may come from the turbo when you are accelerating. Turbochargers gain their power by using exhaust gases to turn an impeller and give the engine a boost of horsepower. It is not uncommon for turbos to develop a whine over time.