Whirring sound as I drive - increased speed = increased whirring sound...

I have a 2008 Toyota Tacoma 4x4 with 98,000 miles. I have started to hear a whirring noise when driving. It sounds like the transmission wont shift (the faster I go the whiring sound increases - like the tranny is winding out). However, the transmission is fine and I can tell it is shifting ok by the feel and looking at the tachometer. Could it be front wheel bearings, one of the Differentials or the Transfer Case? Any thoughts or who (type of garage) I should take it to for a look-see or is it something or a test I can do myself?

 

Carrier bearing

 

Oh and...











Welcome to TW!

 

Thanks robssol, I appreciate your response! I googled 'carrier bearing' and watched a YouTube video on replacement as well. Looks like you nailed it! The "stealership" told me it was my front wheel bearings and quoted me $1500 to replace both.... I was not ready to go with their recommendation before I looked into it and considering the whirring sound (and where I hear it - now that I think about it) I am fairly certain the wheel bearings are fine. Also, thanks for the 'welcome' to TW!

 

$1500
For a fairly easy job! Did both of mine last year, less than 3hrs.