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Hi guys,

I havent had much (any) experience with diffs and my viscous lsd is hammered, so im going to replace the centre with a Kaaz 1.5 way. I was just wondering whats involved in installing an aftermarket centre, and if i could do it myself. Im not an idiot, and have done 98% of the work on my car, so im sure i could do it; i just dont know whats involved because ive never delved into the diff area before.

Does the diff housing have to be removed from the car and then you install the centre while the diff is on a bench, or is it all done while underneath the car?

Is it a matter if putting the Kaaz in the housing, then thats it. Or does someone who knows what theyre doing have to set the diff up? I mean set the tightness of the diff, or is all that done from factory?

Is there anything else worthwhile doing in there while its all apart?

Thanks in advance. I havent even seen inside a diff before, so i just want to get an idea of whats involved, and whether i have to factor in $400 worth of labour ito the purchase price.

Shaun.

You have to remove the housing from the car.

You can replace the center yourself fairly easily but you will not be able to check that everything is right clearance wise.

I did mine myself (nismo 1.5 way) including pressing on the bearings, replacing the seals, swapping the crown wheel over, kept track of everything as it was removed and reinstalled it exactly the same as it came out. Chucked it back in the car and back lash was terrible and it whined something chronic. I never had the time to get it looked at so just lived with it.

recently took it to a diff specialist, it cost me 60 for him to pull it apart, check everything, put it all back together and check the backlash, adjusted the preload on the pinion shaft (what ever that means), chuck in an lsd additive and replace the oil.

I haven't driven it yet, but as this guy has done diffs for a lot of people i know i am sure it will be right. And for $60 it's well worth it in that regard.

If your center comes with new bearings and stuff i doubt you'd pay more than 80 for the center swap.

It's probably a bit out of your way but Langs Differentials in Hornsby if anyone is in that area and needs one done.

You have to remove the housing from the car.

You can replace the center yourself fairly easily but you will not be able to check that everything is right clearance wise.

I did mine myself (nismo 1.5 way) including pressing on the bearings, replacing the seals, swapping the crown wheel over, kept track of everything as it was removed and reinstalled it exactly the same as it came out. Chucked it back in the car and back lash was terrible and it whined something chronic. I never had the time to get it looked at so just lived with it.

recently took it to a diff specialist, it cost me 60 for him to pull it apart, check everything, put it all back together and check the backlash, adjusted the preload on the pinion shaft (what ever that means), chuck in an lsd additive and replace the oil.

I haven't driven it yet, but as this guy has done diffs for a lot of people i know i am sure it will be right. And for $60 it's well worth it in that regard.

If your center comes with new bearings and stuff i doubt you'd pay more than 80 for the center swap.

It's probably a bit out of your way but Langs Differentials in Hornsby if anyone is in that area and needs one done.

Awesome, thanks for that.

Ill take the diff out of the car and take it to a place for them to do. Im sure the $400 was a drive in, drive out sort of deal, so hopefully i can get it done for the sort of priced you suggested. If not ill take it to that place in Hornsby.

Is the diff heavy to remove from the car yourself?

Just make sure you have a jack under the diff when removing it, id say it weights around 20-30kg maybe?

I'd personally guess closer to ~20KG (20-30 sounds about right) if its similar to an R33 GTR diff, its not that heavy but not something you can deal with under the car, put a jack under it :P

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