Installing LSD Into G Series Live Diff

[Smokey228]

Last night I had a go at swapping the LSD Center into my Single Legger G Series live diff. I have never done it before and was always worried it was a lot more difficult. But it seemed easy enough so I gave it a shot…
I figured for anyone else thinking about doing it, this might help. And at the same time, if I have done anything wrong, someone can point it out before I go ahead with installing it back into the car
I started my photos from the point the center was out of the car, but in case you haven’t done this yet, then I’ll give you a quick walkthrough without pictures… In my case I have the MA70 rear brake upgrade so disregard the obvious steps if you retain the standard drums…

STEP 1. (With wheels removed from car and oil dropped from diff)
1. Remove the two 14mm bolts that mount the Calipers to the Caliper Bracket. With some coat hanger, ‘hang’ the caliper from somewhere so there is plenty of slack in the brake line.
2. Once done, remove the 4 x 17mm bolts that hold the axles in the housing. They can be seen from behind the caliper or drum…
3. When sliding the axles out, I had to remove the 10mm bolt that holds the handbrake cable so I would have enough slack the remove the axles from the captive center.
Take note, although you have dropped the oil from the diff, more will probably come out at this point…
4. There are 12 or so 10mm or 12mm bolts that hold the Center Carrier into the Diff housing. Remove all of these bar 1 top one (this will hold it in place for now)
5. Make sure the axles are pushed out far enough to no longer be captive from the diff and position either yourself or something that can take the weight of the center as it comes free. Remove the top bolt and slide the center out. Be prepared for the weight as they probably weigh about 15kgs or more…
STEP 2. (Pics to start. This will remove the open center, from the carrier)

1. Remove the two 12mm retaining bolts that hold the hook in place of the spacer looking thing.

2. Remove the 4 x 17mm bolts that hold the caps over the bearings.
The caps will come free, and may remove the spacer/shim things either with them or leave them on the carrier, either way, remove these as well.


3. The center can now come free.

[Smokey228]

STEP 3. (Removing the crown wheel from the center)

1. There are 10 x 17mm Bolts that hold the crown wheel to the center, all of which have metal brackets to ensure the bolts do not work loose. Firstly gently bend the brackets free of the bolts on every bolt.

2. Once the brackets are free, and you are able to get your socket onto the bolt, undo each one moving in a star pattern around the crown wheel.

3. The crown wheel is usually a relatively tight fit onto the center. As I had no interest in retaining the single legger center, I dropped it against the floor from a couple of inches until the crown wheel fell a few cm; I then used a screw driver to wedge the crown wheel free from the center.

STEP 4. (Installing the crown wheel onto your new LSD Center)


1. Now that you have your crown wheel free and you’re new LSD Center. Place the crown wheel over the center, gears facing away from the mounting plate, and line up each of the 10 bolt holes on both crown and center.
2. Once I had lined up the holes, I used a rubber mallet to get the crown wheel within room to use bolts to pull it closer.

3. I then placed the metal bracket things that hold the bolts in place to ensure they don’t come loose, and then went around the 10 bolts, in a star pattern, tightening them slightly each time. When the crown wheel was firm against the center, I then used a torque wrench and tightened each bolt to 95Nm. (I’m not sure if this is the correct tension, but when un-torque-ing the bolts, they came free at 105-100Nm, so assumed that a few Nm less would be where they were.)

[Smokey228]

STEP 5. (Putting the center into the carrier.)


1. I then put the bearing caps onto the center, and while holding I placed the center as close to equal as I could.

2. I put the bearing caps on and put bolts on finger tight.
3. I then used the shim/spacer things to center the diff center. One at a time, I threaded them on so they would align the caps them self (this is why the caps are loose enough to be moved), and used a screw driver and hammer to work the spacer things around, placing the screw driver in a whole, and tapping the screw driver around a full revolution at a time, from side to side, until they were up against the bearing caps.
4. This is now where you fine tune the centering of the diff center.
I would tighten them until it would take a firm hit from the hammer to move the centering things anymore.
I would then make sure that the pinion wheel can rotate easily the full revolution, I also made sure that the backlash or free play was a bare minimum. I was unable to get it to no free play, as the crown would get too tight against the pinion and lock up at particular point in its revolution.

5. Once I felt that the center was as centered as possible, and that the centering thingy was firm enough, I tightened the 4 x 17mm cap bolts, I used a rattle gun as my torque wrench only goes to 110, and these were tighter than that, so I assume it’s a matter of getting it as tight as possible.
(I left the shim/centering thing/spacer things firm, because when I tightened those 17mm bolts, it also tightens the bearing caps making everything inside slightly tighter.)
6. Put the 2 x 12mm bolts, and their small locks in place and tighten.


That’s all it took to get to where I am now, I haven’t tested as the cars not driving, but if I’ve missed or done something wrong please let me know before I destroy something / else.

My finished product was a center with a smooth spin and no ‘knotchy’ bits, and an incredibly small amount of ‘play’ or back lash. Whichever it’s called…

Cheers,
Jase

[MWP]

VB?? Im not taking notice of anything you say in here from now on

Nice work on writing the guide... but the whole alignment process would have me a little worried.
While i haven't tried myself, plenty of people say to leave it for the diff rebuilding pros as its very hard to get correct.

[Smokey228]

Grrrr, VB is awesome! lol And besides, what validity do you hold, your from SA?

I had my old T Series taken apart and locked by a mate of mine. It lasted 6 months before i snapped an axle off in the center and it bonded and killed all the fun for me...

He is no professional and said its pretty easy and straight forward... But if i've gone wrong, i'd love to know before the center actauly goes in

Cheers,
Jase

[LeeRoy]

Yeh i would have attempted this myself with my f series center if it wasnt for the whole thing on setting up the backlash and meshing of the gears.

Maybe just take it to a diff shop and have them check the mesh to make sure youve done it right. Would suck to throw it in and have it whine like an upset girlfriend.

[Smokey228]

Ahhh, this is a very good idea! I will have to call the local diff shop. See what they say...

Cheers, +rep
Jase

[The Witzl]

yeah - i would DEFINITELY get the backlash set correctly by a diff shop. Without getting it set correctly, it can destroy the centre very quickly.

[SillyCarS]

now withdrawn

[rob]

if anyone is familiar with the "is born" show hosted by Mark Evans one of the episodes of a 4x4 is born details the process of rebuilding the diff and adjusting the backlash

he explains it very well in step by step sequence, you have to take care to do things correctly but there is no ooga booger black magic about it.

no clips of it on youtube unfortunately

[SillyCarS]

now withdrawn

[MWP]

if anyone is familiar with the "is born" show hosted by Mark Evans one of the episodes of a 4x4 is born details the process of rebuilding the diff and adjusting the backlash
he explains it very well in step by step sequence, you have to take care to do things correctly but there is no ooga booger black magic about it.
no clips of it on youtube unfortunately

Forgot about that, its in EP4.
Its a good series to watch... lots of good tips in it.

[Smokey228]

Cheers guys, ive been to busy today, but i'll call the diff shop tomorrow and see if i can run it down there...

I noticed the diff already had paint on it and was being 'ground' off when it was to tight and fouling up...

Silly,
Will show you when i get her going again...

Cheers,
Jase

[LeeRoy]

What exactly can be adjusted to change the backlash?

Im guessing the pinion can be moved back and forward and the crown can be moved from side to side. Can anything else be moved?

Also, if your only swapping the crown wheel, and the bearings where the axles slide in center the crown then it can only be adjusted sideways. So it seems to me like this would be a whole heap easier than setting a diff up from scratch - ie having to install pinion, all planetary gears, the lsd, crown, and whatever else - am i right in assuming this? Not to mention your only reinstalling gears which have alread been meshing for however long so any wear patterns will be present and only have to be realligned.

[fixeruperer]

whats the lsd from ?