325ix Transfer Case DIY ( originally written by juubi)

[nando]

ZF-95a I believe?

the chain is HV-024 for early and HV-024R for late.

it's possible there are a few of them sitting around in warehouses at different transmission places.. maybe I'll get lucky, they're listed at under $200 in a couple places - but you have to call to confirm they even have it. :)

[Nisse Järnet]

Yes both are ZF and i got the price from the Swedish ZF importer :-)
Ill get back with a price on the E30 chain.

Anyone got the ZF part number on the E30 tc btw? Should be a sign somewhere with numbers.

[nando]

it's probably made by the same factory but it's a different width (and likely length).

I'm still hopeful since it's made of commodity parts (standard links), they just add more links for the length and stack them for the width. so they can still make them, but I don't know if they'd want to make a small run of something like 10 or 100..

[Nisse Järnet]

Can you get new chains in europe? Borg Warner says they are NLA. Talking to them to see if that is forever.. BMW wants $1000. :(

My brand new VC was only $578 back in January.

A new chain for E34 is around $600, i can check the price for the E30 text week.

[nando]

Can you get new chains in europe? Borg Warner says they are NLA. Talking to them to see if that is forever.. BMW wants $1000. :(

My brand new VC was only $578 back in January.

[downforce22]

Wow this should be a sticky, i missed this when it was posted last

[imwhyteyo]

Awesome. Used alot of this info today replacing the seals in my 200k+ tc. Luckily my vc was still in great shape(after bench testing). Inside my case was a bit ugly with buildup. But is clean now and leak free.

[jute91]

Thank you for that! :) Enjoy!

[Danny]

I fixed all the images for you.

Thanks for the write up!

[jute91]

Hi all!

I spoke with my finnish friend Juubi about translating his DIY to english... so here you go.. correct my language please :)

Original page here: http://juubi.hlan.net/index.php?page...x/transfercase
So the car is BMW e30 325 -89



Parts used in service:



Seals 2x ( front shaft)

Seal for rear shaft

Seal for input shaft

paper gasket for case

ATF oil 0.5 litre

Transmission oil 1.25 litre



So i noticed need for service when i was driving snowy road with summer tires on. All went fine till
rear end started to slip and torgue was lost from the front end fully to rear. I was able to proceed
moving with lot of throttle but thinking about traction there was no any reason to continue this way.
So viscous coupling located in transfer case has come to the end of its life.



Factory Brand new viscous would cost something around 2000 euros, so that wasn't even a option for me.
Viscous is assembled in the vacuum space, welded by robot, so i thought that it would not be reliable
option to repair it myself. Only changing the viscous coupling makes that much work that changing it
just for a test would be unnecessary. Luckily i found

full TC for suitable price, which had fail on its front axle splines. Transfer case that i bought included
100k km drived viscous, but at this part i could not test it but only rotating by my own hands..



The repair itself started by removin exhaust, exhaust covers, front shaft, transfer case support and rear shaft.



Dropping of the engine was quite fast attempt. Needed to remove front subframe bolts, steering rack,
power steering and radiator hoses. After that i was able to drop engine for transfer case remove.

Dropping of the engine pictured in front of the car.


I needed jack with support tranny so i supported engine with the chain.

After removing all the parts and lowering the engine, i was able to remove the case itself.



Transfer case is bolted to the tranny with 4 bolts, also jointment between tranny and T case has 3 bolts per flange.
Removing these bolt will drop the transfer case.

Transfer case ready for service and change of viscous coupling.



Case had some oil leak from breather and front seal. Glory itself was washed with pressure washer and all hardened oil
was removed from the case before starting to tear it apart.

I choosed best parts from these two transfer case and build it togehter.



After that i was able to start disassemply.



Shell will split after removing all M8 bolts off around shell. It needs little rubber hammer because 2 liners.
on the background you will see car front end and drive shaft of the other side..

Disassemply of T-case



After splitting shell you lift gear off with the puller, rest of the parts will loosen with rubber hammer



Checking chain



My old chain felt little loose. You can measure chain looses by twisting chain on cross-direction,
over 200k km is able to see on this chain.



comparing old chain to newer..

Viscous next to each other



Here is my spare and old viscous. It is impossible to measure the condition of viscous by eyesight but
in this case you couldonly guess which one is cleaner

Now its right time to replace seals to T -case.



There is no any counterface for seals where to tap new ones. You should measure the depth before removing old one.
At this part i used washers to measure correct depth.



To be continue...



After installing all seals, I was able to start put it back together



It all started by installing input shaft to case. Its locked with lock ring.

Then its time for gear and viscous crown.



Then you drop the planet gear onto it.



for a point on a "i" you'll drop the unbroken viscous onto it.



Preparing the rear cover



Chancing rear cover seal is done by same technic like i showed earlier. Using washers.



Here is Ix's saddly failed front output gear. Luckily i got another one with splines that are in good shape.



Installation of chain, i took old bearing from spare T case, which was in better condition.



All things together, ready to install rear cover



Making of gasket



Cover installed



While Transfer case is off, you should check your tranny output shaft seal too and all rubber mounts etc.



then you can start to put it all back together..