Drive Shaft Issues - AW11 + KAAZ DBT2010 LSD install

[nick.parker]

Hello,

I have an issue that is currently perplexing me to the extreme.

I have an E51 Supercharged gearbox case with the guts from an ST205GT4 (E154f) which has the same setup as a late model Turbo SW20, except with a shorter first (grr), but it does have better 2nd gear synchros etc...

Anyway I also have a KAAZ DBT2010 LSD installed and here is where is gets whacky (to me at least). Note a shop did the install for me, as I didn't want to do this job, acquire the tools, possibly screw it up etc

The LHS stub axle (an SW20 late Turbo LSD stub) simply cannot go into the gearbox far enough, as it hits the 'divider/centre stop' in the middle-ish of the diff after going in about 77mm. Comparing to my old E58 gearbox, with viscous LSD (I used the exact same driveshafts) and they can go in the required 100mm. On the RHS, I have a problem also The space is far more that required (the splines are too far away), so the shaft cannot go in deep enough to engage them. I have no idea why the KAAZ / E51 combination is not working.

It is as if the LSD centre is one inch too much to the LHS of the car -- so one hypothesis I have is the LSD head is installed backwards, and then the crown gear is flipped also maybe to keep it in the right spot.....I'm not even sure if that's possible .

Any ideas greatly appreciated.

(NB : I have a swag of picture to add to this post, but the FORUM is buggy (for me) and I cannot attach pictures -- I keep getting asked to login again and post gets lost time and time again.

Nick

[nick.parker]

If anyone has some E51 drive shaft stubs I'd love to know the distance for the end of the shaft (the gearbox end) to the shoulder that stops the shaft going too deep into the box, for both the LHS and RHS stubs, incase that is the answer -- thanks!

[*84vvt]

Think you will need non LSD stubs as the viscous stub is to long.

https://www.youtube.com/watch?v=hELEmjt5Y4k

[nick.parker]

I hope not, I just took the box out this evening!
I found this in the comment section of that video

if its oem lsd trans u will need lsd axles. I have the kaaz lsd, both axles will fit b

So it sounds like any axles should work for the KAAZ (same KAAZ part for AW11SC, SW20turbo and Supercharger Levin), including the long spine LSD versions?

IMG_20220110_200633.jpg (527.81 KiB) Viewed 4092 times

[nick.parker]

The gearbox shop sent me on my way......the guy I spoke to is adamant that I have the wrong axles and wasnt willing to explore any other scenarious.

He might be right. But at the same time, I cant see how the diff would work in the E58 box given how the diff appears to be in the same location relative to the LHS of the box.

So does anyone have some AW11SC axles they can measure for me.....I need to know about the stub shaft dimensions.

[nick.parker]

For reference from my gearbox (E51 + ST205GT4 guts) and SW20 Turbo LSD shafts

LHS.png (372.6 KiB) Viewed 4089 times

RHS.png (258.04 KiB) Viewed 4089 times

[nick.parker]

The plot thickens.......I've been chatting to KAAZ.
My measurements in MAGENTA...theirs in RED......more to come tomorrow....
The measurements are from the outer diff head case to the end of the splines (what they asked me for rather that to the divider plate thing).

both_KAAZ_plus_mine.png (358.18 KiB) Viewed 4083 times

[GDII]

Can you shorten the axle stub?

[nick.parker]

Yes, potentially that is an option for the LHS, and you'd need to make a new C-clip groove, but sadly it cant fix the RHS where the axle would need to be lengthened. At the moment I'm in a holding pattern, waiting for the gearbox shop to check the internals of the LSD aren't incorrectly assembled.

[nick.parker]

So I finally have the answer!!

After having the box completely stripped down and then the diff pulled apart, the internal gear carrier was installed backwards - swapped that over allows the axles to work!!!! It taken a huge amount of labor to sort, but at least I now know the answer and will be on the road soon. So factory assembly mistake I guess. Unfortunately it was a very costly mistake in terms of time and money.\

So in conclusion :

Yes, you can (as expected) use Turbo LSD driveshafts in an E51 with a DBT2010 KAAZ diffferential.

Infact, the turbo LSD drive shafts (WRT to the AW11) work in E51 and E58 boxes with a KAAZ differential. And in both cases, you use the cast iron E58 half shaft support bracket, and of course you'll need AW11SC (or ST185) outer CVs for the AW11 hubs.

[mknz]

Unfortunately it was a very costly mistake in terms of time and money.

Oh no, I guess you ended up having to go to a different shop? At least it's over I guess

[nick.parker]

Yes, I'm glad this has been solved -- it was not fun only being able to guess at this issue, I must have one of the most expensive MR2 gearboxes in history based on money spent (mainly due to bad luck). If I had a more organised or bigger garage (spread the mess) and a few extra tools -- I'll tackle this sort of thing myself in the future, but garage just too clogged up -- being in the middle of installing 9AGZE and also lacking some pullers and Torx bits and gearbox experience and on a timeline (i.e. ASAP!!) Now I can look forward to re-installing everything and soon a test drive!

[GDII]

Glad that it was figured out. Looking back at the dimensions that KAAZ gave you vs the dimensions you have on the axle stubs you can clearly see they match up but were opposite. Amazing that you can install it backwards and it still fit in the gearbox.

[nick.parker]

Yeah -- agree - that was my original line of enquiry - like is this even possible?

Prior to this LSD/diff issue, the 3/4 selector shaft was installed backwards, so the detents were missing -- so the box was pulled apart to correct this also.....this is the third time this box has been apart in about a month fingers crossed its all good now!

[GDII]

Scary!! When you take it to a shop and pay good money you expect it to be done right.