Whine after racing

[SpeedingFirebird]

I raced my car pretty hard doing hot laps around a local road course. The first trip out after that, I noticed a loud whine that sounds like it is coming back the back of the car. It occurs only when accelerating with the tranny engaged.

1. clutch in - no sound
2. clutch in, revving enging - no sound
3. clutch out, no gas - no sound
4. clutch out, throttle - whine.

Any rpm range from what I could tell, and almost any amount of throttle. It is LOUD.

T5, aluminum driveshaft, 3.73 motives with Auburn posi. The rear was rebuilt last summer with NO noise whatsoever.

so far, the suggestions I have are input shaft bearing, carrier bearing, and TOB. Someone also suggested several smaller things to inspect.

I pulled the rear end cap off last night (and replaced with a TA girdle), and I did not see any metal filings in the fluid.

The tranny seems to have picked up a slight vibration as well, but that is probably unrelated.

Can the carrier bearings be replaced easily or does that require someone who knows how to rebuild a rear end?

[ssms5411]

Re: Whine after racing

Carrier bearings I would have someone do who knows how to do it, might as well do the axle seals etc. if it turns out to be your rear, I don't know too much about the Auburn posi's since I have had Torsens all the time, I do have the 3.73 motives also with no whine , I like GM Motive gears ,always have been no noise to them when installed well. Did you check your pinion nut when you replaced the gridle, to make sure it hasn't back out, thats what happened to mine with my 3.42's. It started to make a whine, I never noticed it because it happened slowly . The GM techs and my Dad noticed it when they did my M5 to A4 install.

[SpeedingFirebird]

Re: Whine after racing

Carrier bearings I would have someone do who knows how to do it, might as well do the axle seals etc. if it turns out to be your rear, I don't know too much about the Auburn posi's since I have had Torsens all the time, I do have the 3.73 motives also with no whine , I like GM Motive gears ,always have been no noise to them when installed well. Did you check your pinion nut when you replaced the gridle, to make sure it hasn't back out, thats what happened to mine with my 3.42's. It started to make a whine, I never noticed it because it happened slowly . The GM techs and my Dad noticed it when they did my M5 to A4 install.

At the risk of sounding like a complete n00b, what is a pinion nut? Figures you'd ask after I dumped $40 worth of RP Gear oil in it.

[techsan23]

Re: Whine after racing

I dumped $40 worth of RP Gear oil in it.

The auburn units are designed and tested with conventional GL5. If you switch to a synthetic they will make noise. A high quality 80w90 and some friction modifier (not trans-X) should at least keep it from chattering.

[vr4gasm]

Re: Whine after racing

yup you messed up when you thre royal purple in a auburn rear can not do that even if you drain it now you may have caused permant damage... drain it asap and put some thing non synthetic in and the gm additive and see if that clears it up

[SpeedingFirebird]

Re: Whine after racing

yup you messed up when you thre royal purple in a auburn rear can not do that even if you drain it now you may have caused permant damage... drain it asap and put some thing non synthetic in and the gm additive and see if that clears it up

ARG! :mad: What is this GM additive called?

Is there really that big of a difference between synth and convetional? I put in 75W90 RP.

[techsan23]

Re: Whine after racing

GM#1052358 It does make a big difference in the auburn units, synthetic vs. conventional. I tried synthetic and got alot of chattering: drained and refilled with conventional and GM friction modifier
> no more noise.

[SpeedingFirebird]

Re: Whine after racing

GM#1052358 It does make a big difference in the auburn units, synthetic vs. conventional. I tried synthetic and got alot of chattering: drained and refilled with conventional and GM friction modifier
> no more noise.

Yep, I just found it as you were posting: GM Performance 1052358 Limited Slip Lubricant Additive. How much do I need? 1 or 2 4oz bottles?

I am not getting chattering though. I am getting a loud whine only under load. Certainly, I will drain out the the RP (what a waste of money...) and refill, but I suspect my whine will still be there. Or do you think this could have caused the whine as well?

[techsan23]

Re: Whine after racing

Or do you think this could have caused the whine as well?

Hard to say. Hopefully different fluid will eliminate the noise, but you will find out shortly. One bottle is enough to treat your entire rear axle. I had a little bit of a hard time finding a major brand conventional. Stay away from the coastal brand found at autozone & advance. It is not designed for positrac.

[vr4gasm]

Re: Whine after racing

you only need 2 oz per rear end if you add more your rear will be too slick and you will have slippage issues auburn calls for 3oz gm calls for 2oz

[vr4gasm]

Re: Whine after racing

btw i use the heaviest mobil and 2oz of gm fluid in my auburn and its fine :) the regular mobil is not synthetic

[SpeedingFirebird]

Re: Whine after racing

btw i use the heaviest mobil and 2oz of gm fluid in my auburn and its fine :) the regular mobil is not synthetic

I'll hit up the dealership and auto parts store during lunch. Thanks.

[vr4gasm]

Re: Whine after racing

wait i use lucas gear oil my bad not mobil.. i have used them before though

[VF1Skullangel]

Re: Whine after racing

Last time the rear of my car is whining like it wasn't good. lol!.

[ssms5411]

Re: Whine after racing

At the risk of sounding like a complete n00b, what is a pinion nut? Figures you'd ask after I dumped $40 worth of RP Gear oil in it.

Don't worry you don't have to change fluid to check the nut, its where the driveshfaft hook up to the rear end, I have never heard that about Auburn not able to use syn. maybe because I never had one. I use RP with a little slip diff. in my Torsen and it is smooth running. Guess learn something new everyday.