Gear whine
10-23-2016, 08:04 PM
#1
Gear whine
At 123k on the clock my car has developed a pretty nasty gear whine. Not sure how long its has really been there as my a/c went out about two years ago and so consequently i never drive with the windows up. It just happened to be cold enough the other night on my drive home. Do i have any options other than regearing?
10-24-2016, 12:36 AM
#2
Le Mans Master
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St. Jude Donor '13-'14-'15
I would 1st do a drain of all the diff oil and refill with the proper synthetic rear oil as well as the rear Posi additive ----See if that cures it
10-24-2016, 10:46 AM
#3
Well, I bought this car with 108k on it and the first thing I did was replace all the funds. This car has gaf several owners and I was sure no one else had changed them. So it's really only got about 12k on the current fluid. Think it's gotten bad enough that quick that changing it would make a difference? I do drive the snot out of this car
10-25-2016, 08:57 PM
#4
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St. Jude Donor '13-'14-'15
Well, I bought this car with 108k on it and the first thing I did was replace all the funds. This car has gaf several owners and I was sure no one else had changed them. So it's really only got about 12k on the current fluid. Think it's gotten bad enough that quick that changing it would make a difference? I do drive the snot out of this car
It my not be the rear end at all--It may be a rear half shaft bearing OR a rear wheel bearing !!
10-25-2016, 11:34 PM
#5
I did the gear oil change 100% properly. With additive. But I have not checked the oil level recently. Guess I need to take it in. There has never been an oil slick in the cars parking spot. I doubt it is a wheel bearing. I can feel it in the shifter.
10-26-2016, 11:09 AM
#6
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
If you can feel it in the shifter, it could very well be bad Torque Tube Bearing/s An easy way to tell if its a torque tube bearing is that it will vary with ENGINE RPM.
If it always increases with wheel speed, look AFT of the transmission.
With that many miles on the car, YES, you could very well have a wheel bearing issue. Does the noise change at all if you apply slight LEFT or RIGHT steering input?
If it were me, I would jack up one rear wheel and do some testing:
1. PUSH PULL the wheel at the 3-9 O Clock & 12-6 O Clock positions and see if you have ANY slop in the wheel bearings. There should be little to none. Although NO SLOP doesn't mean 100% that the bearing still isn't making the noise.
2. Trans in Neutral, opposite drive wheel on the ground, TRY to rotate the wheel off the ground CW and CCW. You should feel the limited slip clutches inside the rear end resist wheel rotation and then break free. A new properly operating GM rear will have significant breakaway resistance. A well worn rear with mileage, should still have some breakaway resistance and be equal on both wheels. If you have little or none or one wheel is significantly different than the other, your clutches are worn and or the beleivew clutch preload spring/s are damaged /broken.
(VERY COMMON ISSUE)
BC
If it always increases with wheel speed, look AFT of the transmission.
With that many miles on the car, YES, you could very well have a wheel bearing issue. Does the noise change at all if you apply slight LEFT or RIGHT steering input?
If it were me, I would jack up one rear wheel and do some testing:
1. PUSH PULL the wheel at the 3-9 O Clock & 12-6 O Clock positions and see if you have ANY slop in the wheel bearings. There should be little to none. Although NO SLOP doesn't mean 100% that the bearing still isn't making the noise.
2. Trans in Neutral, opposite drive wheel on the ground, TRY to rotate the wheel off the ground CW and CCW. You should feel the limited slip clutches inside the rear end resist wheel rotation and then break free. A new properly operating GM rear will have significant breakaway resistance. A well worn rear with mileage, should still have some breakaway resistance and be equal on both wheels. If you have little or none or one wheel is significantly different than the other, your clutches are worn and or the beleivew clutch preload spring/s are damaged /broken.
(VERY COMMON ISSUE)BC
Last edited by Bill Curlee; 10-26-2016 at 11:11 AM.
10-26-2016, 07:36 PM
#7
According to the factory shop manual, after changing the dif oil, you must drive the car (as I recall) 300 miles before WOT. Running it wide open before that can result in permanent gear whine. Just sayin, that could be it also. It's a good bet almost nobody does this.
10-28-2016, 05:10 PM
#8
when it comes to break in periods i am very strict. i was a submarine mechanic for the navy for several years and that will almost definately teach you do adhere to the manual. that whole "underneath the water from the get go" thing tends to do that to people. i will jack the car up and do the checks. it does not change at all with steering input. only changes in pitch with speed over 40 mph or so.
i think i am going to go ahead and swap the differential. it was on my to do list to go to a 4.10 gear. and with the miles that are on this car i think i am going to swap in a refurbished unit. that way i can get new diff clutches and bearings and the whole nine yards
i think i am going to go ahead and swap the differential. it was on my to do list to go to a 4.10 gear. and with the miles that are on this car i think i am going to swap in a refurbished unit. that way i can get new diff clutches and bearings and the whole nine yards
10-28-2016, 08:42 PM
#9
Drifting
Where in the shop manual did you read this?
10-29-2016, 06:14 PM
#10
Racer
Rearend noise
If you can feel it in the shifter, it could very well be bad Torque Tube Bearing/s An easy way to tell if its a torque tube bearing is that it will vary with ENGINE RPM.
If it always increases with wheel speed, look AFT of the transmission.
With that many miles on the car, YES, you could very well have a wheel bearing issue. Does the noise change at all if you apply slight LEFT or RIGHT steering input?
If it were me, I would jack up one rear wheel and do some testing:
1. PUSH PULL the wheel at the 3-9 O Clock & 12-6 O Clock positions and see if you have ANY slop in the wheel bearings. There should be little to none. Although NO SLOP doesn't mean 100% that the bearing still isn't making the noise.
2. Trans in Neutral, opposite drive wheel on the ground, TRY to rotate the wheel off the ground CW and CCW. You should feel the limited slip clutches inside the rear end resist wheel rotation and then break free. A new properly operating GM rear will have significant breakaway resistance. A well worn rear with mileage, should still have some breakaway resistance and be equal on both wheels. If you have little or none or one wheel is significantly different than the other, your clutches are worn and or the beleivew clutch preload spring/s are damaged /broken. (VERY COMMON ISSUE)
BC
If it always increases with wheel speed, look AFT of the transmission.
With that many miles on the car, YES, you could very well have a wheel bearing issue. Does the noise change at all if you apply slight LEFT or RIGHT steering input?
If it were me, I would jack up one rear wheel and do some testing:
1. PUSH PULL the wheel at the 3-9 O Clock & 12-6 O Clock positions and see if you have ANY slop in the wheel bearings. There should be little to none. Although NO SLOP doesn't mean 100% that the bearing still isn't making the noise.
2. Trans in Neutral, opposite drive wheel on the ground, TRY to rotate the wheel off the ground CW and CCW. You should feel the limited slip clutches inside the rear end resist wheel rotation and then break free. A new properly operating GM rear will have significant breakaway resistance. A well worn rear with mileage, should still have some breakaway resistance and be equal on both wheels. If you have little or none or one wheel is significantly different than the other, your clutches are worn and or the beleivew clutch preload spring/s are damaged /broken.
(VERY COMMON ISSUE)BC