Worn LSD?

BrianZ
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Worn LSD?

Postby BrianZ » Sat Nov 08, 2014 2:43 pm

So for all these days I thought my 86 doesn't have a LSD...

When I bought the car, I was told by the owner it doesn't have a LSD and he was pretty sure about that. So I figured he must have found a way to know it. And I didn't bother to check the fore wall for that code. And I did tried to drifted it in a rainy day in a empty parking lot but I counldnt have it go side way. BUT with my girlfriend in it and over size wheel (tend to rub the fenders when I make hard turns), I was by no means hard on it.
I bought a rebuilt oem LSD unit couple days ago and thought, hell, let me check the fire wall, then BOO
T283. From my understanding 3 stand for LSD and 2 stand for non LSD.
Then I texted the previous owner, he said he jacked it up and spinned the wheel and they rotated in the opposite direction.
I know for Torsen or helical rear end it would act like a open diff when it is jacked up. And I know the AE86 came with clutch type LSD.
So I wonder if the LSD is worn ? Or that's the way it should act?

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jondee86
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Re: Worn LSD?

Postby jondee86 » Sat Nov 08, 2014 3:07 pm

Find a place where you can stop the car with one rear wheel on
concrete or other clean tarsealed surface, and the other wheel
on loose dirt or green grass. Let the clutch out quickly enough to
spin the wheels. If the car sits there with one wheel spinning
and just crawls away, you don't have an LSD. But if you have to
work a bit to spin the wheels and the car pulls away much the
same as usual, you do have an LSD.

When the clutches are worn in a factory LSD (no pre-load), it
behaves much the same as an open diff when testing it with the
car on jack stands. You have to get some load on the diff to get
the cam working on the ramps before the clutches will bite.

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

MisterJerk
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Re: Worn LSD?

Postby MisterJerk » Wed Nov 12, 2014 7:43 am

you should be able to see the diff with the fill plug out. if you see pinion gears, its an open diff.

ZINCHOTRAN
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Location: East Wenatchee, WA

Re: Worn LSD?

Postby ZINCHOTRAN » Wed Nov 12, 2014 7:22 pm

On the question of worn out LSD.

If you can break traction in a left hand turn, but not break traction to the right, is your LSD worn out and in need of a rebuild? And yes, it is mine.

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jondee86
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Re: Worn LSD?

Postby jondee86 » Thu Nov 13, 2014 1:46 pm

ZINCHOTRAN wrote:If you can break traction in a left hand turn, but not break traction
to the right, is your LSD worn out and in need of a rebuild?

I guess the LSD must reach a point where it is so worn that it will no
longer lock up one side ? But it could also have something to do with
the torque reaction of the rear axle, which tends to unload one wheel
(right rear IIRC).

Does it spin the right side wheel when turning right ?

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

ZINCHOTRAN
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Posts: 147
Joined: Mon Jan 14, 2013 10:52 pm
Location: East Wenatchee, WA

Re: Worn LSD?

Postby ZINCHOTRAN » Thu Nov 13, 2014 8:06 pm

I will need to set up a video camera to record it. Thanks for the recommendation.