I too, have heard the noise in the front hub (only once or twice). But my 4 wheel drive hasn't even been working. I have had it "fixed" at least 2 times (think its actually been 3) by my personal mechanic (not Ford) and it still doesn't work (I have found out the hard way 2 of the times). After over $300-$400 each "fix" this is getting a bit ridiculous. It this is a common problem, why isn't Ford correcting it (for free) like they did with the "advisory" (not recall) on the older model doors (when they were all cracking)??? It's deer season and bad weather is imminent and I need to have the 4x4 (we all probably know how worthless a truck is without it and no weight in the back). Any input would be helpful.