Current builders for Quaife/Wavetrac front differential?
 

I have a project for which I want to build an E53 front diff with Quaife or Wavetrac limited slip.

What experiences do members here have both driving with such a unit and building the diff in the first place? Has anyone driven both Quaife and Wavetrac?

What shops will assemble and setup the diff for me?

I found some related threads searching:

https://xoutpost.com/bmw-sav-forums/...ferential.html

https://xoutpost.com/bmw-sav-forums/...p-lockers.html

https://xoutpost.com/bmw-sav-forums/...ted-slips.html

https://xoutpost.com/bmw-sav-forums/...and-build.html

Update….
 

I swapped out my rear differential for a Quaife version that I built about a year and a half ago. The car behaves much better on the slippery and muddy roads and farm tracks that I end up on while bird hunting. I was expecting a modest improvement, but it’s actually eye watering how much better the car behaves when things get really messy. The DSC does a fine job on we roads, etc., but the car use to get sideways in a flash when all wheels started slipping. I try to not get into anything really nasty, but after a couple years of using it I have gotten into some pretty slippery stuff, both on and off road.

The Quaife just works seemlessly with the DSC/ABS too. Before I would get into some ice covered muddy roads and end up sliding sideways with the ABS hammering away uselessly. Now the ABS hits once or twice, which allows the Quaife to get to work transferring torque. It all happens in a flash, and the rear end just straightens out and the x5 moves forward.

I was worried about the front differential, and the transfer case too being open diffs, but frankly I don’t think I would stick a Quaife in the front diff now, if they even made one that fit (I don’t think they do). It all works so well for what I do that I don’t think it’s necessary.

I’m serious when I say that if I built it, so can anyone. It is not rocket surgery. I’m closing in on 2 years with mine and it hasn’t blown up yet. That said, there is so little reading available on rebuilding our 188k medium diff versions that i made a lot of assumptions. It took me a while due to my sked, so I just bought an eBay diff and took my time. I posted a lot of pics and explanations on my overland posts here and on bimmerforums.

You’ll need a set of shims for our stupid 188k diff case version. Quaife says it should work with the OE shims, but mine wasn’t close. The Quaife is a fantastically well machined piece of gear (literally), but you are working in fractions of millimeters. Racing Diffs in Eastern Europe sells a set of snap ring shims and has lots of videos online to view, and was very willing to give me advice.

There is a diff shop in Massachusetts (I think) who said he’d build it for me, but I can’t vouch for the shop as I didn’t use him.

Happy to provide more feedback and lessons learned.

Update: the diff rebuild starts on pg 23ish
https://xoutpost.com/bmw-sav-forums/...-build-23.html

I bought the output bearings from Diffs Online (I think), and he said he’d be happy to build it for me too.

I didn’t mess with the pinion in the eBay donor diff as it wasn’t leaking and the pre-load tested fine, and although I ended up with a tiny bit too much lash in the diff, so far it hasn’t caused any problems. You’ll need a press to get the pinion out.

As I said, the silly snap ring shims our diff cases use came from Racing Diffs. He machines a set of 8 or 10 shims, if I recall correctly, of different sizes. The shims accommodate minor differences in the diff and case, and bearing races I suspect, in order to get the correct pre-load and gear lash. Too thick and the diff won’t go in, but I recall reading that it is tough to put too much pressure on-load on a diff, so I found the combination of two shims that gave the correct lash, but were a challenge to get seated.

Thanks!
I must have just looked at the last photo on that page (post 230) without realizing it was a rear diff rather than front.


The front is a 168mm unit. The E53s use the QDF6N. It has to be split and the gears turned around in order to operate in the correct direction.


I've worked on diffs before. I just have other things I'd rather do with my time. The front case is a clamshell design, which makes checking the pattern much fussier than it is for the rear differentials, which makes the setup process more tedious.

Interesting. The rear is a QDF13N. I found a YouTube of a Brit rebuilding his front differential and the bolt count on the ring gear was fewer than the rear differential ring gear. I assumed it was a smaller unit then. Quaife didn’t have info on which, if any of their diffs would fit the e53 front. Originally I wanted to do both front and rear.

Do you have a helical diff in the back, and still want one up front? My x behaves so much better with the Quaife rear differential that I dont think that for what I do that I need it. Although, my front differential is leaking a bit, so if and when it comes out I could capitalize on all your lessons learned and build one!

How is the front diff shimmed?

The Quaife sales literature shows the QDF6N as being used in the Z4. It would make sense I guess that bmw would have designed the front diff housing in the e53 around a diff they were already using. A smaller carrier, but that makes sense too in the sense front diff handles less torque in the x5.

I need to find that YouTube video again and see if he gives a parts list, where to buy the parts, and if I can see any shims, etc, come out when he disassembles it.

Found the video…5:26 mark shows the ring gear bolted to the diff carrier.

https://m.youtube.com/watch?v=fP30Em9kado

That should make the job easier since it doesn’t need to be cut off. The video also shows the the output flanges each have a spacer under them. Not sure if spacers for a z4 diff would work, assume the Quaife would need different thicknesses then the oe diff.

I’m sure a machine shop could make them, however.

The 2002, E21, 4 cylinder E30s, and, by extension, 4 cylinder Z3's received various versions of the 168mm rear. BMW recycled it into the E53 X5. The different versions had different widths across the carrier bearings. The 2002 width went into the front of an E46 (or maybe E34?), while the E21 & E30 width went into the front of the E53.


The front drive axles are very different than rear drive axles. That's another aspect of the project I'll have to tackle.

Yeah, that's the unit. It's very similar to, but not interchangeable with, an E46 front diff.


Edit: The "spacers" he was talking about are the carrier (and pinion) bearing shims.

Edit2: Installing a Quaife means that the carrier bearing shims will probably not be re-used. That means the clamshell case will have to be split multiple times, reading the gear pattern each time, in order to select the correct carrier bearing shims. Getting a readable gear pattern for a gear set inside a clamshell housing is the kind of tedium I don't need in my life.

Also, 200C is pretty hot... I would think that's risky for hurting the heat treatment of the bearings. I don't know if he consulted the bearing manufacturer or not.
Going colder than freezer temperatures for the cold parts doesn't hurt, though.

Ok, I guess I need to go find Jim Blanton.




Drexler diffs are wild! I had not heard of them before.

Do you light up one front tire on a regular basis? I can't say I remember ever once having that happen in 8 years of E53 ownership, not even during the short period where I was dumb enough to drive on all-terrain tires in the snowy winters. The early E53s only have something like a third of engine torque sent to the front axle.