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Diff thuds on accel/decel

HoldenHoon

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Hi everyone, I have a 2000 vx v6 ecotec and I just had an issue where as I got to accelerate or when I’m slowing to come to a stop I can hear a thud noise in the diff (LSD). it is very apparent as you can literally feel it in the floor. I have already serviced the diff with pro gear 80-140 and I have also added limslip additive but it’s still there. I also found that when I’m reversing and I have the car full locked it feels as if one axle is jumping/skipping? You can both feel and hear it too. I have already replaced the diff mount, reconditioned both driveshafts and I have reconditioned the Tailshaft centre bearing and unis including the rubber donut couplers. What am I missing as it is doing my absolute head in!! Any advice is appreciated! Thanks
 

krusing

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Possibly welded !
or
LSD clutches are jamming up
or
Spring Tension not adjusted correctly
or
The New Centre Bearing is cactus.
 

HoldenHoon

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Possibly welded !
or
LSD clutches are jamming up
or
The New Centre Bearing is cactus.
I just checked the centre bearing is still alright, it’s definitely not welded as you can hold one wheel and spin the other but it takes a fair bit of force to hold one side and spin the other it was fighting me to spin, I have also noticed that both diff axle stubs have movement up and down, the drivers side makes a bit of a thud as I move it up and down and the passenger side has movement but it doesn’t make any sound, could a worn down axle stub make a noise as bad as this? Thanks.
 

krusing

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I think you have answered your own question,
The Diff side bearing plates need to be adjusted,
another option was to say Hub bearings & CV's.
 

HoldenHoon

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So it basically needs to be pulled apart and rebuilt? Thanks
 

krusing

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If all the hardware is ok,

Hmm, Yep !
 

HoldenHoon

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If all the hardware is ok,

Hmm, Yep !
I did a bit of research and some people online are saying you can adjust the play from the outer cap? Its located where the axle stub slides into the diff, it’s a circular ring with cutouts and people are saying to locate which axle stub is noisy and to tighten that side up 1 notch at a time and to take it for a test drive. Does anyone have any thoughts on this? I couldn’t really care about ruining my diff since it’s probably shagged anyways. Thanks.
 

HoldenHoon

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Could I adjust this? Or is that not part of the issue? No backlash in the diff it just makes a thud sound from the drivers side stub axle when I turn the Tailshaft back and fourth.
 

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Immortality

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No.

The side adjusters alter bearing pre-load and adjust the back lash (gap between) the ring gear and pinion.

There is nothing to adjust on the stub axle, it runs on a small needle roller bearing inside the side adjuster behind the oil seal.
 

Immortality

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Could I adjust this? Or is that not part of the issue? No backlash in the diff it just makes a thud sound from the drivers side stub axle when I turn the Tailshaft back and fourth.

Maybe the LSD is worn and allowing a lot of movement internally.
 
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