2008 Diff Swap - specific question

Nova2013 · Post by **Nova2013** » Mon Feb 18, 2019 10:09 pm

Hi All. I am a new z4 owner and I am swapping my 3.23 to 3.73. I have the old one out (parts labels and bagged). I am generally particular about that kind of stuff. HOWEVER, A spacer came out from the rear bolt and I am unsure which side of the mount it goes on. It is aluminum. Any help would be appreciated.

I attached a picture for reference. I looked up parts diagrams and haven’t gotten anywhere. Anyway. Thanks in advance.

Nova2013 · Post by **Nova2013** » Mon Feb 18, 2019 10:32 pm

Ok. I just put the new diff in and tightened the front bolts. There was a slight space where I ended up putting the shim ( see picture). Can someone verify this is correct? I feel pretty good but any help is appreciated. Thanks again.

adam1985 · Post by **adam1985** » Wed Feb 20, 2019 4:50 pm

I think you have it in the correct place there is some discussion here viewtopic.php?t=76459
im sure GuidoK will be along to confirm

Yorkie Z · Post by **Yorkie Z** » Wed Feb 20, 2019 5:34 pm

Yeah looks about right. How come you changed your diff?

Jembo · Post by **Jembo** » Wed Feb 20, 2019 5:46 pm

Yorkie Z wrote: ↑Wed Feb 20, 2019 5:34 pm Yeah looks about right. How come you changed your diff?

Pretty serious first post compared to my bonnet sensor question... plus has pictures.

Welcome, am sure someone will be along to advise

GuidoK · Post by **GuidoK** » Wed Feb 20, 2019 7:33 pm

The spacer needs to be placed indeed between the bushing and the mounting lug on the diff case:

Nova2013 · Post by **Nova2013** » Wed Feb 20, 2019 11:29 pm

Sorry guys. Been offline for a day or so. Thanks for the replies and info. I generally can’t leave well enough alone. No issue with the rear differential. Just wanted to taller gear ratio. The car is a 6 speed manual with a 3.23 ratio... went with a 3.73 to provide more torque. I finished last night and test drove it in the rain. So far, so good.

I also refinished the wheels (bad curb rash when I bought it). They look new and despite being time consuming, it was fairly easy.

I know there is a lot of discussion about repair manuals or lack thereof. I found a couple of posts with TIS manuals but I sure hate the format. Any other suggestions?

Thanks again for all your help.

Nova2013 · Post by **Nova2013** » Wed Feb 20, 2019 11:39 pm

A few pictures of the before and after of the wheels.

GuidoK · Post by **GuidoK** » Thu Feb 21, 2019 12:39 am

Also interesting to see that they changed the rear diff bolt in 2008. It has an unthreaded shaft. The earlier models had a full threaded shaft, which is weaker as I broke that one in the past.

Nova2013 · Post by **Nova2013** » Thu Feb 21, 2019 1:51 am

Did not know that. Do you use an online TIS manual? Are mechanics able to purchase repair manuals that individuals cannot?

GuidoK · Post by **GuidoK** » Thu Feb 21, 2019 2:35 am

I sometimes use the online TIS (which is great, https://www.newtis.info/), but mostly I use the old DVD install TIS on one of my pc's, which I find easier to use.
(its mainly faster when clicking the links and the interface is a little bit different:

Sometimes I use the TIS part of ISTA-D (that also includes TIS), depends on if I have that program open on my pc.
TIS in ISTA:

As far as being able to purchase TIS: Nobody can do that except official BMW dealers.
All versions of TIS that we see (whether the online one or as an install on your pc) are pirated versions.
Everything you read/see/hear about TIS, ISTA, INPA, NCSexpert,WDS etc are all pirated versions as it is proprietory bmw (factory and dealer) software.

But the online TIS version should get you by in all workshop manual related stuff. That link also includes WDS (wiring diagram system)

Liam22 · Post by **Liam22** » Thu Feb 21, 2019 11:18 am

I also hate the TIS system.

I like to have service manual printed and in front of me for some jobs. Usually I just want torque values overlaid on an exploded diagram view (like Mazda do).

Any experience with this PDF offering?
https://www.emanualonline.com/Cars/BMW/ ... rrency=GBP

Nova2013 · Post by **Nova2013** » Thu Feb 21, 2019 1:48 pm

Thanks again. I haven’t purchased anything on eBay yet but plan to. I’ve enjoyed the forum. Look forward to learning a few things.

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