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Old 02-26-2019, 06:32 PM   #1
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bad grinding in corners

99 base 2.5L, 5spd manual with 120k miles.

in tight corners with heavy throttle I hear a bad grinding noise from the rear end, like dragging steel pipe over a concrete floor. It does not happen with light throttle or in long sweepers.

I don't see anything obviously binding or grinding. All suspension pieces are brand new. I'm thinking the most likely culprit is a bad CV joint (boots are clean, no grease leaking) or maybe a bad wheel bearing (they don't seem loose when I rock the wheels with the suspension unloaded).

any other thoughts?

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Old 02-27-2019, 02:39 AM   #2
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Wheel bearing would be my first inclination as well.

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Old 02-27-2019, 03:05 AM   #3
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+ 1 on wheel bearing

Yes, with 120k miles it could well be a wheel bearing, better to replace both sides.

They are not too expensive (Pelican) and you will have a lot of fun replacing them..
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Old 02-27-2019, 05:05 AM   #4
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Lol thanks. I have all the tools including a 12 ton press. 😁
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Old 02-27-2019, 05:58 AM   #5
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there is a test for wheel bearings. while you have the car on stands, also check your diff.
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Old 02-27-2019, 07:16 AM   #6
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How does one test wheel bearings? I thought it was to grab the wheel at 3 and 9 with tire off the ground and see if it feels loose
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Old 02-27-2019, 07:37 AM   #7
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Smile Grinding sound

When you have the Car on stands, a few simple wheel spins and you can listen and feel
for unusual grinding sound. Done this on a few occasions on my other cars. Hope this helps.
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Old 02-27-2019, 07:57 AM   #8
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Quote:
Originally Posted by jmitro View Post
How does one test wheel bearings? I thought it was to grab the wheel at 3 and 9 with tire off the ground and see if it feels loose
ah - i re-read your initial post - you did test them and no movement. personally, i think that since the noise is proportional to the amount of power applied, that it happens in tight turns yet the the rear wheels don't turn, that you may have to look to your diff - you get the sound when one wheel is slipping perhaps.
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Old 02-27-2019, 04:58 PM   #9
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It could also be your center motor mount. Mine sounded similar only on hard throttle in tight corners. Have someone follow your car and see if the tail pipes move a lot when you get on the throttle hard. Or if the shifter moves a lot when you get on it.
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Old 02-27-2019, 07:59 PM   #10
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My motor mount also sounded like grinding when turning. If it hasn't been replaced by 120k...I'd do that first.
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Old 02-28-2019, 04:04 AM   #11
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Definitely. I have a laundry list of repairs to make and motor/transmission mounts are on it. Hopefully the problem is not the diff.
Thanks all for the replies!

Last edited by jmitro; 02-28-2019 at 04:07 AM.
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Old 03-29-2020, 05:57 AM   #12
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thought I would update this thread with a note that replacing the motor/transmission mounts cured the grinding noise, so it was definitely not the differential
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Old 03-29-2020, 08:31 AM   #13
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I have a grinding noise caused by bad transmission and motor mounts. Occurs when under heavy acceleration in first and second gear.

Have the parts, just need time to replace them.
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Old 03-29-2020, 01:43 PM   #14
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Quote:
Originally Posted by jmitro View Post
thought I would update this thread with a note that replacing the motor/transmission mounts cured the grinding noise, so it was definitely not the differential
Glad you got it sorted out

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