pinion bearing going bad?

i will try the neutral thing today. also, for my own reference...what is it that exactly that is making this sound? just the bearing? the gears not meshing well? at work we have a ford exploder with about 150K on it. it makes the same sound, only about 15x louder. if i put my radio up around 18 in the taco, it covers the sound so its not tooo bad yet.

 

The bearing being loaded and unloaded. I wouldn't worry about it. Just check the fluid, and let it be

 

yeah i checked the fluid today since it was warm for once. its full, and looks clean.

 

Resurrecting this thread. My truck is doing this same thing. This morning the howling noise was so bad on or off the gas or coasting that I pulled over. Came to a rough stop. Rough take off too, could hear/feel something not going right in the rear end. Look under and it was leaking out the bottom of the diff and steaming hot! Checked the oil and it was almost gone. filled up with 2 quarts and limped home. While limping home going downhill in neutral I coasted to 50 mph with no more bad screaming rear end or vibrations till I put it back in gear and then the loud noise back when I was on the gas or not. Sound like just a bearing? Does whole 3rd member need replaced if it ran low and heated up? Tearing the 3rd member out now to inspect.

 

It's not a bearing noise or it would do it all the time letting off the gas would not help. All rears make some gear noise you are more likely to hear it in a pickup than anything else just by design (no sound deading and the bed to amplify it). When the ring and/or pinion are bad or maladjusted the whine is pronounced under load or coast a faint wine is normal under certain load conditions. It’s up to you weather you lose sleep over it. My 2011 had a faint whine at highway speeds brand new it still does at 47K has not changed a bit. A differential is probably the last thing to fail on a vehicle provided it’s not abused or run out of oil.

 

i'll contribute to this thread again. truck has 120K on it now, the noise is still there. no louder, but still present. i stopped losing sleep over it lol

 

I ripped out my 3rd member and my pinion is shot. You can see sharp metal on the edges where it was shaving away the gears. Also a nice pile of debris in the bottom of the diff, mostly gasket seal and metal shavings.
Now I'm in the market for a 8" 4.10 e-locker 3rd member.
Brand new 3rd is $700-$800 or parts to rebuild $400-$500 and I don't have a press to so the work.

So yeah, go change your oil today and keep an ear out for noises! Little longer and I'd need new shafts and wheel bearings too. Wish I could have caught this sooner :/

 

Junkyard?? Or what about east coast gear supply?

 

I found a 8.4 taco rear axle with Detroit lockers and a Dana 44 front with detroits, both $1000 I'm thinkin snag them and do sas down the road.
Ecgs is $700 for 3rd swap
Haven't seen anything at a junker, found a used 3rd for $450 needs pinion bearing...
Decisions decisions...

 

So i've decided to man up and rebuild it myself. Gonna pull the trigger on a press, ring and pinion, and master rebuild kit. Any suggestions to what brand of gears and rebuild kit I should go with?

The axles mentioned in the previous post were sold

I have a 2002 8" with e-locker, do I have a 27 or 29 spline pinion?

 

I had the 4 leaf pack installed at 89k & developed that same noise...my third member was replaced with a new one at 96k....under warranty. 199k now no issues