1999 Blazer - Strange Sound Front End
 

On my way home today, driving 70 MPH, I noticed a strange sound which seems like its coming from the right front passenger side area. I sounds like when you hit the rumble strips on the road, you can hear it for a few seconds and then it stops, then it comes back again. I heard the sound at 70 MPH and down to 10 MPH.

I have a video with the sound but can't upload til I'm home.

Engine light is on but its only the P0410 code. ABS light is not on, truck runs good, etc. I don't hear anything when I make a sharp right or left turn.

Looks like it wasn't the wheel hub assembly, it's possibly the transfer case. I noticed a small leak in the seal few days ago, doesn't look bad at all and only been leaking a short period of time. 5 days ago I got stuck in mud, put her in 4 wheel high, no go, put her in 4 wheel low and got right now, but not without a loud bag up front. I don't off-road so the truck isn't abused. I simply drove up to a creek and there was two big ruts. Anyways, the noise in LOUD and constant. I put it in 4 wheel high and the noise isn't there, put it back in 2 high and it sounds like gears are grinding, still have power, it takes off but the noise is there.

Anyone run into this before?

Found out the problem, turns out the guy that rebuilt the tranny, didn't add any transfer case fluid. We added a quart and a half, so basically was dry. No more noise.