Noise on Test Drive
#1
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So I test drove a beautiful 2002 SOM Manual Trans Am. Car looked great and was only $9,000 bucks and had 68,000 miles on it.
Here's the bad parts. When accelerating above 45 mph, I heard a whine. Is this normal or does this indicate the rear diff is going out? I took my flashlight and looked underneath and saw a tiny wet spot on the rear diff. Did not have a chance to smell it since I could not get under there.
Is that whine I heard the rear differential? And is it bad that I heard it?
Here's the bad parts. When accelerating above 45 mph, I heard a whine. Is this normal or does this indicate the rear diff is going out? I took my flashlight and looked underneath and saw a tiny wet spot on the rear diff. Did not have a chance to smell it since I could not get under there.
Is that whine I heard the rear differential? And is it bad that I heard it?
#3
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If it's going to be mainly stock or a bolt on car and your not going to beat on it real hard (lots of track time, clutch bumps with a tire, etc) you can generally find a replacement 10 bolt on here or locally for $300-$400. Dont let people scare you by telling you the 10 bolt is glass....lots of people putting up good times on their 10 bolts. I sold my factory 10 bolt with 27K miles on it to a member here for $300 IIRC.
If you want to spend some money you got S60, 12 bolts, 9inch, etc.
If you want to spend some money you got S60, 12 bolts, 9inch, etc.
#4
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So I test drove a beautiful 2002 SOM Manual Trans Am. Car looked great and was only $9,000 bucks and had 68,000 miles on it.
Here's the bad parts. When accelerating above 45 mph, I heard a whine. Is this normal or does this indicate the rear diff is going out? I took my flashlight and looked underneath and saw a tiny wet spot on the rear diff. Did not have a chance to smell it since I could not get under there.
Is that whine I heard the rear differential? And is it bad that I heard it?
Here's the bad parts. When accelerating above 45 mph, I heard a whine. Is this normal or does this indicate the rear diff is going out? I took my flashlight and looked underneath and saw a tiny wet spot on the rear diff. Did not have a chance to smell it since I could not get under there.
Is that whine I heard the rear differential? And is it bad that I heard it?
Did it sound like it was coming from the rear?
Was it a whom whom whom sound or more like a high pitch constant weeeeeeeeee or what?
Could also be wheel bearings or the tires themselves depending on what it sounded like.
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As for the wet spot on the diff, that's extremely common. Most of these have some weep from the pinion seal, or it could be a bit of weep from the cover gasket if not properly installed. Of course, if the tiny wet spot is all that's left of a once really BIG wet spot that has since dried up due to running out of lube - well then that's bad.
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I agree, it could be many things based on the vague description, probably not possible to diagnose over the internet unfortunately.
As for the wet spot on the diff, that's extremely common. Most of these have some weep from the pinion seal, or it could be a bit of weep from the cover gasket if not properly installed. Of course, if the tiny wet spot is all that's left of a once really BIG wet spot that has since dried up due to running out of lube - well then that's bad.
As for the wet spot on the diff, that's extremely common. Most of these have some weep from the pinion seal, or it could be a bit of weep from the cover gasket if not properly installed. Of course, if the tiny wet spot is all that's left of a once really BIG wet spot that has since dried up due to running out of lube - well then that's bad.
^^ This...
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In regards to these later model vehicles, specifically LS1 F-bodies, I've found that sitting isn't nearly as bad as some people tend to suggest (assuming the car is still maintained properly for its role, with fluid changes and occasional usage and such.) I owned my '98 and '02 Z28s side-by-side for about a decade, during which time the '02 was my daily driver and the '98 was (still is) my garage queen. Truth is, the daily driver '02 developed many more seeps/weeps/leaks and generally worn parts from the rigors of ~110k miles of daily usage and heat cycling than the '98 ever did from sitting.
Regardless, a 68k mile 15 year old car isn't going to be the victim of disuse related problems, unless those 68k miles were all done in the first few years and then the car sat totally untouched, poorly stored and non-maintained for the next dozen years or so.
#10
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Thanks for all of the responses. I decided to pass on the deal. I just don't have the time or money to mess around with something like this. Next year.
The sound was coming from the back when driving. It happened only on acceleration, and was best heard over 45 mph. It sounded similar to a supercharger whine. The whine was constant on accelerating. Not like a wom wom wom. But like a weeeeeeeeeeeee.
Tires didn't have any flat spots. Passenger rear brake sounded a bit scratchy.
The vehicle was already warmed up when I got there as well. I definitely prefer a cold start. I didn't tell him until an hour before that I prefer a cold start so he said he already had the vehicle on when he moved it to wash it.
Thanks again for all the responses. The car is on cars.com if anyone thinks it's a deal. I'd probably buy it if I had the time to fix it myself or extra money to pay someone to look at it.
The sound was coming from the back when driving. It happened only on acceleration, and was best heard over 45 mph. It sounded similar to a supercharger whine. The whine was constant on accelerating. Not like a wom wom wom. But like a weeeeeeeeeeeee.
Tires didn't have any flat spots. Passenger rear brake sounded a bit scratchy.
The vehicle was already warmed up when I got there as well. I definitely prefer a cold start. I didn't tell him until an hour before that I prefer a cold start so he said he already had the vehicle on when he moved it to wash it.
Thanks again for all the responses. The car is on cars.com if anyone thinks it's a deal. I'd probably buy it if I had the time to fix it myself or extra money to pay someone to look at it.
Last edited by YeahPete; 06-21-2017 at 08:39 AM.
#13
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I put 196,000 on my 99Z and it whined from day one, I did notice a change in pitch and took it in and it had a bad wheel bearing that ruined the axle also, this was still in warranty at the time. Gotta remember the differential is enclosed in the cabin....
#14
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I've owned 6 and they all did it, some louder than others. I test drove a bunch and they all whined to some degree. My present WS6@ 145k has always done it. I'd say its normal as long as there are no other issues going on.
#15
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I've owned 2 and none did it. I've test driven another 4 and only one of those didd it. So that's 1 out 6. Very annoying on that 2000 SS with 74K miles...sounded like a fighter jet taking off at higher speeds.
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None of my four have ever had this issue either, but they were all autos. I think the M6 cars are more prone to developing this.