Very slight grinding noise from rear?

I opened my sliding rear window today and noticed a very very slight grinding noise. The noise does not vary with engine speed. The noise starts around 20 to 25mph. Doesn't matter what gear it is in. This noise is very slight. Had a friend drive it and at first he didn't hear anything, but later he did. He said it might just be a normal noise for the differential or rear brakes.

At first I thought it may be wind noise, but I am not certain of that anymore. Anyone else experienced a very slight grinding noise from the rear end? It isn't very obvious.

 

The older one gets, the more likely your rear end will grind.
If still under warranty, take it back to dealership.

 

So not from a rotating part, but requires vehicle motion above a certain speed.

Seems more reasonable. Try different things. Tailgate down, tonneau open, etc. and see if it changes

 

The truck just turned 12k miles.

Correct. The noise is only when truck is rolling. RPMs and/or which gear it is in seem to have no effect. I can be in neutral rolling at 25mph or higher and the noise is there. Again, this is a very slight noise. Barely noticeable.

 

Rear diff? Drive shaft? U joint? Only way to tell is to lift it up in neutral and start moving things.

 

I had the same noise. Toyota replaced the 3rd memeber. Noise came back after 100 miles. Took it back in and now they say its normal... Idk is this light metal sound normal?

 

A lot of moving parts including suspension on a sprung truck. You’ll drive yourself nuts chasing down every noise. I like to drive it until it leaks and/or breaks.

 

All three 3rd gens I've rode in have this noise to some extent. I don't know if its "normal" but it's god damn annoying. I've noticed mine gets much louder driving up the hills to go camping to the point where my passenger and I both couldn't stand having the rear window open for longer than a minute or so. I brought it up during a drive with a tech and he said it was normal...at least I have it documented I guess..

 

I got that same high pitch whirring noise. Initially I thought it was that dif howl that everyone talks about, but it doesn't sound the same. Mine also comes on above 30mph and I can only hear it with the rear window down.