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      01-11-2011, 06:56 PM   #1
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How do you know if your LSD is working properly?

Background... I had the rear LSD "grinding" issue which was fixed via a fluid change. Over the last week or so, it has mysteriously come back but is MUCH worse. The car almost vibrates when accelerating in tight right turns. Turning to the left doesn't have the grinding or vibration.

So, my question, how do you know if the LSD is actually working properly? If it went bad/broke, how would you know? What would the signs be?

Appreciate any feedback.
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      01-11-2011, 07:57 PM   #2
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that doesn't sound normal, the car should not vibrate while accelerating and turning under any amount of steering angle unless you are sliding (and even then you wouldn't feel it vibrate badly unless it was understeer, rear oversteer/wheelspin does not feel like "vibration")
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      01-11-2011, 08:15 PM   #3
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jack the car up and spin one back wheel, the other should spin in the opposite direction.
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      01-11-2011, 08:32 PM   #4
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Quote:
Originally Posted by Serious View Post
jack the car up and spin one back wheel, the other should spin in the opposite direction.
Or maybe it should turn in the same direction. Opposite direction would mean it was a NON-LSD.

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      01-11-2011, 08:41 PM   #5
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Drive it in the snow and you will notice when you turn or skid.
I often notice the LSD when I do full throttle after accelerating out of corners.
I can feel one wheel is spinning faster than the opposite one.

Some people notice it easily and some don't. Good luck.

Last edited by LemonOne; 01-12-2011 at 11:13 AM..
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      01-11-2011, 09:01 PM   #6
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Quote:
Originally Posted by Radiation Joe View Post
Or maybe it should turn in the same direction. Opposite direction would mean it was a NON-LSD.

hmmmm you sure? i too always thought it should spin in the opposite direction?
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      01-12-2011, 09:34 AM   #7
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An open diff (non-lsd) rotates opposite to the one being turned. A limited slip differential uses clutches to semi-lock the spider gears of the differential together.

LSD = wheels turn the same direction
open diff = wheels turn in the opposite direction

no clutches below:

[u2b]<object width="640" height="390"><param name="movie" value="http://www.youtube.com/v/p0kz96c6iUU&hl=en_US&feature=player_embedded&versi on=3"></param><param name="allowFullScreen" value="true"></param><param name="allowScriptAccess" value="always"></param><embed src="http://www.youtube.com/v/p0kz96c6iUU&hl=en_US&feature=player_embedded&versi on=3" type="application/x-shockwave-flash" allowfullscreen="true" allowScriptAccess="always" width="640" height="390"></embed></object>[/u2b]


How differentials work.
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      01-12-2011, 10:52 AM   #8
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Quote:
Originally Posted by Radiation Joe View Post
An open diff (non-lsd) rotates opposite to the one being turned. A limited slip differential uses clutches to semi-lock the spider gears of the differential together.

LSD = wheels turn the same direction
open diff = wheels turn in the opposite direction


How differentials work.
Correct
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      01-12-2011, 11:21 AM   #9
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cool video
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      01-12-2011, 11:31 AM   #10
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I know my LSD is working when my dog grows wings and starts flying around the room.

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      01-12-2011, 12:16 PM   #11
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When I had a Type-R I'm pretty sure they spun in opposite directions?
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      01-12-2011, 12:33 PM   #12
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Quote:
Originally Posted by Serious View Post
jack the car up and spin one back wheel, the other should spin in the opposite direction.
You got it backwards. That's what an open differential does.
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