Whirring Sound

I tried searching the forums but didn't find anything definitive on this sound that I am hearing. Its almost like a 1-2 second whirring sound (like something is pressuring up) when I am backing up and shift into DRIVE and wondering if its normal? Typically happens when I shift into DRIVE and go, makes this slight whirring sound very slightly and then stops. Any ideas? Normal?

 

Normal, it's the truck's ABS. If you hit a big enough bump/pothole in the road you'll hear the same noise.

 

yep, should only do it once per trip.

 

Thanks for the replies! That makes sense on the noise.

 

What engine do you have?

 

I have the 4.0L engine. I wish it was my turbo spooling up unfortunately Toyota didnt include one .

 

Ok it is as mentioned it is the ABS going through its checks. 100% normal.

 

there's a TSB for that