How-to: Installing a Wavetrac LSD into a 3.73 differential

[roninsoldier83]

I finally tackled a project I’ve been day-dreaming about for a while: pulling a 3.73 diff out of a junkyard donor, tearing it down, swapping in a Wavetrac LSD, and bolting the whole thing into my 128i.

I documented every step — from removing the original 3.23, to cleaning and rebuilding the junkyard unit, to the install itself — complete with tips, photos, and lessons learned along the way. If you’ve ever wondered what’s involved in doing your own diff swap (or if it’s even worth it), this is the write-up you’re looking for.

Check it out here:
https://www.investigatingtheapex.com...ential-rebuild

Whether you’re planning your own swap or just curious what’s involved, hopefully it saves you some headaches (and maybe a few curse words). Feedback, questions, and your own experiences are welcome!

EDIT: To anyone that runs across this thread- I cancelled my blog, but I transferred all the DIYs I wrote into the GRM build thread that I started years ago:

https://grassrootsmotorsports.com/fo.../258441/page1/

[mkeiser]

Nice write up! I found the Harbor Freight 12in Icon snap ring pliers to work great.

[Blau]

Originally Posted by roninsoldier83

I finally tackled a project I’ve been day-dreaming about for a while: pulling a 3.73 diff out of a junkyard donor, tearing it down, swapping in a Wavetrac LSD, and bolting the whole thing into my 128i.

I documented every step — from removing the original 3.23, to cleaning and rebuilding the junkyard unit, to the install itself — complete with tips, photos, and lessons learned along the way. If you’ve ever wondered what’s involved in doing your own diff swap (or if it’s even worth it), this is the write-up you’re looking for.

Check it out here:
https://www.investigatingtheapex.com...ential-rebuild

Whether you’re planning your own swap or just curious what’s involved, hopefully it saves you some headaches (and maybe a few curse words). Feedback, questions, and your own experiences are welcome!

Amazing. Bookmarked. Thank you for the hard work and the great write up!

[juanri]

Blog seems to be down, hopefully it'll be back up since I was using it as a reference beforehand. Great writeups.

[Suprgnat]

Originally Posted by juanri

Blog seems to be down, hopefully it'll be back up since I was using it as a reference beforehand. Great writeups.

https://www.1addicts.com/forums/show...7&postcount=48

[roninsoldier83]

Yes, I canceled the blog. Although I took all of the DIYs I wrote on the blog and transferred them to the GRM build thread I started a couple years back:

https://grassrootsmotorsports.com/fo.../258441/page1/