And yesterday the work continued. Started off by cleaning the mating surfaces for the LSD diff/cover and sealing that bad boy up to prep for the fluid/install.
Also wire brushed the exhaust flanges to make sure they get a nice seal when I reinstall. You can see the gasket material that has come off on this one.
And all downpipes all cleaned up
Then it was time to get into the meat of the work. Unbolted axles and driveshaft from the diff and managed to slip it out by unbolting and turning the swaybar. For anyone wondering, I have not removed the wheels or axles during this removal. I would also note, I would HIGHLY suggest getting a Harbor Freight transmission jack or equivalent if you plan to do this job. It's just so helpful in so many places and I believe I got mine for $50 used.
While I had it all out I decided to replace the metal giubo. I've had some weird vibration issues and there have been suggestions that the metal giubos may cause issues, so I figure it couldnt hurt to just reinstall a rubber unit.
Then I moved on to the most dreaded part of the install... bushing R&R. Ended up renting a ball joint press from O'reilly but still had to go buy some all-thread, nuts, and spacers to make it work. Long story short it all worked out. To note the Z4 bushing sat different than the e46 that I ended up installing. And to be clear in case anyone else has the same question and can't find an answer (basically me for the past few weeks), E46 DIFF MOUNTS FIT. This really opens up your upgrade options, as basically nothing is available but the stock units for the Z4, but there are TONS of upgrades for the non-M e46. I was resistant to go too firm, but you've got options all the way up to solid with the e46 stuff, and there's no indication of them being cross-referenceable. Unfortunately I forgot to take a picture of the new bushing installed, but if you refer to the upcoming "installed" picture you can see how the fitment is slightly different. Same net effect, just bushing sticks out a bit farther on one side, which doesn't effect alignment, function, or install at all.
There was a moment there where I got lazy and thought about not doing the mount replacement, but I'm SUPER glad I did. Once I got that thing out I realized how much flimsier it is than the Meyle unit.
Finally the final step of the big work, moving that gigantic beast into place. Once again, I simply do not see how I would have gotten this done without the trans jack, but after about 30 minutes of struggling she was bolted into place. Thankfully I'd just done all this work on my e30 about a year ago, so it was very similar and I'd already had quite a bit of experience.
Managed to bolt up axles, driveshaft, and the sway bar before finally calling it quits for the day. To give an idea of time spent on this so far, I spent about 4 hours on Saturday and maybe 7 hours of Sunday. At this point it's mainly just buttoning things up to be completed. Final torquing of all the drivetrain bolts, reinstall heat shields, exhaust, and braces/covers... that's about it. Figure I've got another hour or two left in her. Super excited for the outcome of this! The benefits of course being:
- No more exhaust rattle
- Firmed up drivetrain with the stronger rear diff mount
- Eliminated vibration witht the giubo replacement?
- Better acceleration with the shorter final drive
- More grip and predictability with the LSD!
Will have updates on these very soon.