popping noise when i turn corners in my 2003 nav

sounds like you axles are going bad...have someone shimmy under there to see torn boots and leaking grease~

I would check the steering linkages and ball joints.

for some reason a "rebuilt" axle with both boots and grease in there already put together is cheaper than buying each constant-velocity joint, the boot and special dilithium grease putting it together....with the labor and special clamps...presses needed for the job is a darn sight easier to buy the assembled one...a word of caution with regard to pulling the old axles out of the case, as occasionally the retaining clip stays inside the case and you'll need a dental inspection mirror to even see it....good luck on these~

here's new and remanufactured...would not tell me if all four axles were the same....probably just one...the left side?...take a looksee~