yep thats what I have...when you let off the gas....I suspected it was a shoddy job putting in the 4.56 gears that caused my issues...checked my fliud a few days ago and found it was loaded with metallic......figures.....gonna be a pricy fix for me being I cant just swap with junkyard with because of the gears.

 

generally the noise from a bad pinion bearing will change pitch on acceleration vs decel. also, when drive shaft is disconnected, if you can rotate the yoke back and forth, it'll have a dry, loose, noisy feel to it.
if its not pinion then it could be carrier bearings or worn out ring/pinion.

you might put it up on stands and use a stethoscope or pipe to listen to different places on the case to try and pin down the noise. i tried that awhile back on my daughters 4runner and just couldn't tell anything. the noise was echoing up and down the drive shaft so bad. also be careful, i about tore off a leg on a tire.

unlikely it will break. it could run another 100k without any further problem other than increased noise. if you haven't already done so, remove the cover, look it over and put in 90w140 synthetic gear oil. the heavier oil might quieten it down a little. don't expect miracles.

 

My pinion bearings wore out on my at 110K. It felt like it had turbo lack when I would gas it. That is, when I would hit the gas, it would take a while to respond. when my mechanic fixed it, (a good friend of mine) he said that I was lucky that it didn't lock up on my when I was driving.

 

just curious as i believe im having the same problem or mabye worse?about 99.5% of the time when i go from a stop and give it a little gas it goes to about 1500rpm and am barely rolling.keeping in mind when i bought the truck it had 280,000 at first i thought it was the tranny but i had it checked out and its fine but i did find out that the guy i bought the truck from never changed any of the fluids since

 

When I would hit the gas, it would hold up for a sec and then go. It wasn't an aggressive launch. The stealership said it was the WHOLE diff. they wanted to charge me $1500. Such bull.

 

lol stealership they wanted$ 2000 here in alberta to fix mine and i cant even find a used rear diff for under 1200

 

DAMN!!! I guess I got off REAL lucky. There's a bone yard over here that has a half off sale every month. I found out about it by word of mouth since they don't advertise. I'd suggest that you do the same. You never know whats out there. Best of luck!!!

 

well I pulled apart the rear diff today and the gears look great..... did find pieces of a washer or flat clip stuck to the magnet though..( i will have to investigate further)..I refilled the diff with the heavy lucas gear oil and it made absolutly no change in noise tone at all.....

 

ahhh. you have a limited slip ?

be sure and add the little bottle of friction modifier to the oil, or it might chatter.

lsd's tend to drop broken clips from the clutches. they all do it.