Ocamaro.. to be totally honet, changing the fluid isnt gonna help. You will always hear the noise. The rear of a camaro is like a tunnel, you will hear the howel. I almost guarantee that changing the rear diff fluid will not help you.. I had the same problem. I changed my fluid using Lucas Gear Oil. The stuff is thicker than gorilla snot, no difference. The sound you hear are your gears grinding together. I bet you there is play in your rear end. When you enguage the clutch, do you jear a banging noise, kinda like a clunk? That is the play in the gears. You may try and tightening up the nut on your rear end, The nut that is between the rearend housing and where the drive shaft bolts in. What you do is take outthe 4 bolts that hold in your drive shaft to your rearend. *******Besure your rear wheels are blocked or your E-brake is on.Or the car will roll****** The four bolts are 10mm . Once they are out drop the shaft outta the way. There will be a nut about an inch and a sixteenth (1 1/16) or 1 1/8. Before you try and tighten it,not too much, you will burn out the gearsif you over tighten them.try and see if the rear yolk (thats where the drive shafts bolts into) has any play meaning if you can pull it towards you. If you can, depending upon the travel dont waste anytime changing the fluid. If it moves slightly, slightly meaning a 1/4 inch or so, no big deal. Then consider putting a thicker fluid in the housing. And using the TFPE or what ever Banks calls it, also know as Teflon tape, I have never in my 20 years experience used it. You can, it wont hurt anything, but you wont benifit by it. If you do deceide to change the fluid, make sure before you drain the rearend that you do get the filler plug out first. Cause if you can get it out, you cant fill it. All you need is a ratchet wrench with a small extention. No socket, the end of the extention fits into the square spot. If you need any sugestions on replacing the rearend, let me know. Hopefully this helps...

 

What you are describing is called coast howl, When you decelerate the ring and pinion mesh on the backside "coast side" of the teeth. The noise is caused by excessive backlash, which is caused by worn bearings. There is nothing you can do aside from overhauling the rearend. If you have ANY! play at all in the pinion, tightening the nut will only cause more damage. IF THE PINION IS LOSE AT ALL THE BEARINGS MUST BE REPLACED! What you all must realize is the service life of todays bearings is about two to four years, about 70k to 90k miles, a bit more if it is serviced once a year. A lot of times what I find when I get into them is bad pinion and left side carrier bearings, the left side takes most of the load. If you have a clutch type L/S you should be serviceing it every 30k to 50k anyway, and on those little car axles, One 6 or 8oz. bottle of friction modifier is sufficient, too much COULD adversly affect the oil, provided you are using the 6 or 8oz. bottles that we use.

 

well the problem is that i changed the bearings just a month ago and the whole month the car have been sitting and not driving more than 100-200 miles so how could the bearings be worn out if i havent driven the car, in that case the mechanic that changed those did a ****ty job i guess right? or thats not the problem......i dont know...

 

well i dont hear the, clunking sound at least , wierd grinding...well the first shop i went to said that i needed to swap out the rearend and it would cost me 1000 bucks, i just hope that the diff fluid change is gonna make me sure the other step is to change the rearend i guess. if the diff fluid change helps me i just saved 1000 bucks...