KAAZ LSD - Clunky Clunky?? Solutions?

[nastylilweed]

Hey Everyone,

The KAAZ 1.5 way in the back of my Sprinter has got what I think is death clunk. Fortunately I have never had issues with diffs before, unfortunately this means I'm trying to work out if there is an in the mean time solution before going and getting a new center...

Explanation of Problem

The diff clunks on acceleration and deceleration both in straight lines and while turning, this is more noticeable at low speeds.

IE

In second gear, 40km/h and in a straight line the sequence would go like this...

Accelerate, clunk, punch throttle, clunk. It would appear to me that as long as positive pressure is applied through the diff there is no noticeable noise, it only occurs as positive pressure is released and reapplied.

It's a considerable clunk not just a panzy clink, it still lock up very crisp as I would expect it to. IE I don't think it's a worn clutchpack issue.

SO I have come to the following conclusions,

- It's Spider Gear backlash (New center)
- It's Pinion / Crown Wheel backlash (Readjust / rebuild)

My question is, will running a different oil potentially help reduce this issue? My main concern is that it has a TRD Crownwheel and Pinion in it (IE expensive) and don't want to destroy them in the case that I need a new center.

Any help would be super rad!

Cheers,

Joe

[CRONIK]

Easiest way to check pinion to crownwheel backlash would be to grab the tailshaft and twist it back and forth to feel how much play there is. It should have a bit of play between contact but not much.

Other possibilty could be axle tramp? you havent lowered the car recently or set the diff on a funny angle so the pinion isn't facing straight to the gearbox/tailshaft?

[nastylilweed]

Thanks man, ill check the tails haft movement. On the note of play when I had the rear up in the air the other day playing with suspension I was looking at the play in the axle. The wheels free spin about 10-15mm when turned... It seemed a bit excessive which is another reason I thought it may be spider gears...

And no, not recently lowered or played with. It appears to be sitting in line with the gearbox output...

Thanks for the reply,

[maxhag]

Hey Joe,

I bought a Brand new KAAZ 2 way, had it professionally setup in the housing, did the wear in as it said on the KAAZ instructions, and used the KAAZ oil supplied with it.

It did the exact same thing as you have described. And I do mean exact.... It did it for 2 years (then sold the rear end. (R31) ), but the diff performed very well the whole time. It was a very good LSD centre as far as performance..
Oil changes never had metallic particles......

Some of the clunks sound pretty nasty hey, and I always thought something was gonna break, but it never did.

Thats all I can really say to help you.......

JoJo

[nastylilweed]

Hmm that's pretty suspect hey. I have heard many stories of people saying that after market centres are noisy and concerned about the horrible noises they made. It's weird that it would happen from new after everything was set up correctly...

I have read a couple of posts etc suggesting that a different oil has reduced the noise. Which tbh I'm not concerned about noise, I'm concerned about what the noise means and the shenanigans it may be causing, and in that light less noise equals less nasties.

Is it possible that it's clutch pack movement in the cage that's creating the clunk? It seems like a legitimate answer but I'm not sure if it's practical...

I'll do an oil change this weekend and see what difference it makes and if there are any nasties...

Recommendations and experiences with clutch lsd oils? I've head red line works well in these?

[maxhag]

I just always used the KAAZ oil when I had that KAAZ centre. Used to buy it off Ebay......

[nastylilweed]

Thanks man, I don't even know whats in it at the moment and it's probably due for a change anyways... I'll get onto it this weekend and report back if there are any nasties.

Anyone else got any knowledge they feel like sharing?

[maxhag]

A few years ago I did find a video on you tube. It was in America, KAAZ in a 180sx, and it was clunking the same as ours..... The guy was asking for help, but there wern't any replies....

[johl]

from the symptoms i would say your lsd is fine. its locking up so i would say your problem is backlash. i had these exact same noises coming from my old car whenever i was came on/off the throttle. it is a 2 minute fix to adjust the backlash but thats once the centre has been removed. i just took the entire assembly still in the nose cone and a mate fixed it up for me.

as mentioned above turn the tail shaft and see if there is excessive movement, or if you have a decent shop near you it would take a few seconds to put it on a hoist and have a mechanic feel the tail shaft and he will tell you if its too loose

[Prime86]

Hey Joe

I know of a few cars that are fitted with the Kazz 2way centres and from new they do the exact same thing. I know the guy who owned the car before you and was asked by him about it also as it did it from the day it was fitted. When he fitted the new diff he put rose jointed rear trailing arms in the car also which made it 10 times worse so he removed the arms thinking it was them making the noise. I'm actually surprised its still in there as he told me he was going to change it for a TRD centre or Cusco as they don't clunk or bang as they lockup and unlock.
If your worried about it I would suggest removing it as you can just pull the diff hat out with the gears etc to check it properly. It's easy to do takes about 2 hours if your working slow and you don't need any parts to do so. That way you can check the wear in the diff gears, axle bearings and the centre itself along with checking backlash for piece of mind. I would steer away from the old just give the tail shaft a clunk back an forth as there could be another problem down the line with uni's etc, check the parts individually to isolate the problem. I have all the specs if you need any just give me a txt.

[Rice86]

it will do that, its a LSD designed for track use only, not catered for street cars in anyway, another example are coilovers

[Delazy]

Remove it, sell it, replace with TRD

[Rice86]

i was just about to say the same lol, TRD best ive had for street car that sees the track

[nastylilweed]

Haha yeah I heard it had rose jointed stuff in the rear... Pity it's still not fitted.

I'm not too concerned about the noise, I'm concerned about what the noise means and the potential of a shenanigans inside my diff.

I may rip it out on the weekend and see whats going on. I've pulled apart many diffs before so it shouldn't be an issue, I just haven't really come across this kind of issue before..

Thanks for the help gents.

PS Prime86 have I been talking to you via sms already?

[timbo]

My TRD 2way sounds similar, but when I account for no sounds deadening, carpet or back seats it doesn't seem so bad. I've been told it's all normal and have recently added some Penrite limslip additive which helps for noise and feel. Maybe try the same? It's cheap.

[Prime86]

Rice86 and Delazy are on the money, sell the Kazz and get a TRD centre. I seem to remember giving the same advice only days ago...Lol.

I myself run a TRD 2way diff, it's great with no noise and works very well on and off the track.

Yeah Joe...Brad with the pistons etc you wanted to buy and the Kouki coupe.

[nastylilweed]

Haha yeah I got the feeling it was you!

The advice still stands, but there are other things I'd like to be spending money on at the moment. If it's not going to be causing any harm I'll leave it in there for the time being and deal with it in a month or two..

[maxhag]

Johl, its NOT a backlash clunk.... Its differant.... Very hard to describe, but its not backlash

[Prime86]

Haha...Well I suggest just dropping the oil making sure there is no metal in it and if that's the case buy some good quality oil to put back in. If there is no big whines and only the clunk chances are everything will be fine. But when you get the money change it out and you will be much happier with the car.

[maxhag]

Yes guys, we know TRD are the best way to go, but just saying to go get A TRD and ditch the KAAZ, is copout and hardly helping the particlaur issue at hand......

[nastylilweed]

^^ Haha it does however solve the problem... TRD centers really are pretty awesome.

Like I said I'll do an oil change this weekend and ad some limslip, a lot of people have recommended that to me... I'll accept the knock and carry on trashing piss out of it till it dies...

[Prime86]

We aren't saying the TRD is the best just it's known to perform very well and is quiet in its operation. That's is what we all know as it has been proven time and time again. We also know that Kazz are very noisy in many different cars or applications and if Joe wants the noise gone it maybe a better option is to move to a different centre.
I actually thought the advice I offered was pretty good, remove the diff hat and check everything out so he is happy everything is working as it should and the backlash so in his mind he is happy it won't fail in the time he has to decide what he wants to do. The other option is to do an oil change, check for metal and put new oil in also a good option however the noise will still be there.

[sundee]

KAAZ lsd's are "violent" in the way they engage, they are either on or off.
They have larger plates and more of them the most other LSD's.
KAAZ recommend changing the oil at every engine service interval using a good Mineral oil.
DO not use synthetic oil in KAAZ centres!
I have ran in a KAAZ 2 way in a 180sx, during the run in it was very smooth but after its 1st track day it got very noisy, the guy didn't do an service after that day, which is why I believe it's so noisy.
The initial service is key.

TRD and Nismo I have owned both, not as aggressive as KAAZ.
Bang for buck though, you can't go past a KAAZ Center... They now make their super Q design, guess it stands for super quite?
Not offered in every model though.

[johl]

fwiw i have had nothing but awesome experience with cusco lsd also.
from what i remember reading many years ago the most to least vicious engagement was-
tomei
kaaz
trd-cusco on par.

from a quick google i have read alot of people getting positive results from using kaaz branded oil. but that is expensive im sure

does it sound like this?


http://www.youtube.com/watch?v=ESbtUjsTSIg

[maxhag]

KAAZ lsd's are "violent" in the way they engage, they are either on or off.
They have larger plates and more of them the most other LSD's.
KAAZ recommend changing the oil at every engine service interval using a good Mineral oil.
DO not use synthetic oil in KAAZ centres!
I have ran in a KAAZ 2 way in a 180sx, during the run in it was very smooth but after its 1st track day it got very noisy, the guy didn't do an service after that day, which is why I believe it's so noisy.
The initial service is key.

TRD and Nismo I have owned both, not as aggressive as KAAZ.
Bang for buck though, you can't go past a KAAZ Center... They now make their super Q design, guess it stands for super quite?
Not offered in every model though.


The clunks/noises that JOE and I are talking about, IS NOT THE USUAL "noisy" diff n oises that come from KAAZ centres.... Differant from what you mentioned Joel. Yes, they are know noisy diffs, but the clunks that is in question here is totally differant.....
I know thats a bit vague, but unless you have experienced this, its really hard to expalin...

The clunks in question sound simular to a broken axle etc (or something broken inside)..... Sounds very wrong, very loud too........
Yet, the operation of the diff is perfect.....

Every other car with a KAAZ diff I have been in, has been noisy, but not clunking like we are talking about....

[nastylilweed]

The noisy operation doesn't worry me at all if it's normal, I just want to know what it is in case it isn't!!!!

I have been googling youtube videos etc to get a decent video of the noise. I might try and record something myself just as an example. It sounds like there is about 20mm backlash between Pinion and Crown Wheel...

Either way I'm sure I'll get it sorted, just wanted to see if other people were experiencing the same noises...

[maxhag]

hmmmm, ok, well mine was DEFINATLY NOT a backlash type clunk.....

[AJPS]

johl

cusco do the rs type with springs to make engagement even smoother/daily friendly

[sundee]

I reckon they might trash them selves if they are not serviced regularly.
My comment before was Direct from KAAZ in regard to servicing.
Every time you change your engine oil, change your diff oil.
I'd like to take one from new and service it as per the recommendations and see if it makes a difference.
I reckon it will, after the one in the 180 that I installed had the flogging at the track, and the oil was not changed its operation started to get clunky and noisy.

It's clunking because the plates are slipping .