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Question about welding lsd diff.

Jimoffy

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I’m going to pick up a 3.46 diff for my vt commodore. Has the 4 bolt flange already so should bolt straight in. I have a welded diff at the moment but it’s got 3.08 diff so can barely grab second. My question is are you able to weld an lsd diff? Are there inspection ports on it as the open diff has?
 

Jimoffy

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Dedicated burn out pig?
Yes it is. I welded my last one. Just don’t wanna buy this and find out the lsd is **** and I am unable to weld it. This is not a street car
 

vc commodore

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Yes it can be welded
 

immortality

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Just swap your welded centre into the new diff

This is your best bet then you can sell the LSD centre and make a little money back.

LSD centres don't have the open windows in the housing so welding will be a lot more difficult, not impossible but definitely more difficult.
 

Jimoffy

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This is your best bet then you can sell the LSD centre and make a little money back.

LSD centres don't have the open windows in the housing so welding will be a lot more difficult, not impossible but definitely more difficult.
Thanks for that. I heard to swap a diff Center you have to set backlash.. that the only problem I’m facing
 

immortality

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Yes you do but it's not that difficult on the IRS diff as the adjustments are threaded. Mark both adjustment hubs before removal. Drain the oil, hold the pinion so it can't turn and move the crown wheel backwards and forwards to feel the backlash. Then remove the centre, swap em out and put it back. This is only a skid pig so this isn't critical, a touch more is ok but don't go tighter than it originally was. If the gears are a little noisy it really isn't going to matter.

There is a thread in the how to section about identifying and stripping diffs with decent instructions which might be of help.
 

_R_J_K_

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I though the pinion was held in place by the flange? If you're only taking the centre out it shouldn't effect backlash?
 
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Deuce

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I though the pinion was held in place by the flange? If you're only taking the centre out it shouldn't effect backlash?
Crown wheel will come out, pinion gear will not, but he will still need to get the screw in side bearings to the same positions and similar adjustments.
 
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