BIGJON

Ok I have changed the gear oil in the rear axle of my other car... 1991 RS Camaro... and I still have a whining sound only when the gas is let up and in motion... like under acceleration there is no sound... but when target speed is reached.... 30, 40, 50 mph... and you let off the gas to coast I get this whining sound from the rear axle... its an open diff. and its like a 3.08 or something like that with the 700 R4... But I am wondering if the rear end is going out or if its a bearing or what... again I started hearing the sound and changed the oil and no difference... there is no performance difference either... any ideas? I am still learning about rear axles so I am a little stumped... I searched for a while and am still out in the blue....

Tibo

iTrader: (15)

I am going through close to the same problem. Make sure all bolts are torqued down to start out with. It could be the drive shaft is out of balance or the u joints are saying good by to you. It could also be that the backlash on the pinion gear is now out of adjustment.

hoogabooga

iTrader: (1)

my 3.08 did the exact same thing until it locked up and left me stranded.

cam-

Something is wrong with the pinion bearings/pre load. Remove the driveshaft and pinion nut/yoke/companion flange. Next yank out the carrier keeping the caps and shims in order. This is VERY important do not mix and match caps or shims! Then remove the pinion and examine the bearings and replace as nec. Get a brand new crush sleeve form the dealer as you need a new on to set preload properly. Install the pinion gear with repaired bearings and new crush sleeve. Tighten down slowly ( VERY HARD TO TURN BE WARNED ) when the play is all gone very slowly going little by little measure the torque it takes to rotate the pinion with an inch pounds torque wrench and tighten until it takes about 8-10 inch pounds for used bearings and 18-22 inch pounds if they are new bearings. Be sure to not use an adapter for sockets here as this messes up the reading. Reinstall carrier as removed. Add lube. GO racin!

VILeninDM

can you go with solid spacer instead of the crush sleeve? I think they give you some more strength and you don't have to tighten as hard (in the beginning) since you don't have to crush it. any of this make sense?

Also after you remove the carrier, can you just check to see what the preload is instead of tearing everything apart? Although if gear teeth are good, my guess would be bad pinion bearing (but then again I am still yet to do my first rear end rebuild)

cam-

Yes you could do a solid spacer and yes it would be stronger but its time consuming and a little tricky if you have never done it before. Especially considering he already has a aproblem with his pinion he cannot trust that his crush sleeve is even close to whats required in terms of a dimension. You need to make your best guess on a shim and install and measure the rotational torque and remove and repeat as nec until you get the right readings. Certainly doable but adding a little more complexity to what is already a little tricky in the first place.


BTW I forgot to mention that you really should replce the pinion nut with a new one also as they are a one time use item.

BIGJON

Hmmm what a wierd sound though.... it sounds like a transmission whine but its coming from the axle... what would be my options for getting a limited slip for this rear end? I know its an open diff. but I don't know the ratio.... I would like to just get a posi though... could I make something of this?

cam-

Yep no problem to change carriers. That is assuming you are dealing with a ten bolt cause nin bolts are hard to find parts for. Any 7.5" ten bolt posi will fit you just need to match your carrier to the gears which in your case is easy cause its a two series and they are more easilly found for a low buck. ebay? The only diference to the whole procedure aside from the obvious is to shim the carrier for pattern. Searching on here will get you all the info you need for that in terms of how to shim, what posi's fit etc. Good luck