VLSD Broken?? Horrible clunking noise!

[RPS1392]

So after finally getting my car on the road. Today was the first time Ive driven more than just down the block and back. It started as I rounded a corner a few blocks from my house. The longer I drove it, the louder/worse the clunking from the rear got. It only makes noise when turning under power or decel. Around a corner in neutral, it makes no noise.
I almost thought that I had left the lug nuts on one wheel loose. First thing I did was check the oil level. I had changed it a year or so ago when I installed the rear susspension sub-assembly. The Rear end is out of an R32 GTST. The oil level was fine. It is really hard to break loose. With only one rear wheel on the ground I tested the LSD by turning the other wheel. I almost couldnt do it. After this I jacked up the car and checked all the bolts, including the driveshaft, axles, and lugs, all were tight as expected.

Any insight would be appreciated. I searched and read several posts, but found nothing that matched my issue.

[DirtyS14]

Are the axles or flanges rubbing on anything? or is the sound coming from inside the diff?

Was it known good when you got it?

[deuceforty]

as for the clunking, my R33 lsd only does that when it gets VERRRRRY HOT

i drove 20 hours straight over 1200 miles and only near the end when i would decel would it clunk, i wouldnt say it was horrible, but it was noticeable for my passenger

i just chalked it up to heat...

other than that, mine performs very well, ive had nothing but comments, locks up amazingly :)

good luck man :(

[RPS1392]

Are the axles or flanges rubbing on anything? or is the sound coming from inside the diff?

Was it known good when you got it?

Came from Japan in a container, so no history.

http://i76.photobucket.com/albums/j11/yesd0g/Project%20240/RyansPictures132.jpg

[racepar1]

Have you looked at your subframe bushings. Torn subframe bushings are common causes of rear end clunks.

[S14GE]

WORD! check those subframe bushings..

[wangan_cruiser]

i have a rear end clunk. i always hear it whenever i shift gear. its crazy but im about to replace my axles since my boots are torn. but other than the i dunno yet.

[Fonix36]

that means you might as well weld that shit then the clicking will be normal and you wont have to worrie about it lol, but just check the bushng home boy is right.

[RPS1392]

Ive been in a car with torn subframe bushings, and this noise is not like that. In forward or reverse, and only when turning. Like for instance, turning into my driveway at around 2 mph. And the noise is rotational if you get my meaning. I was backing out of the parking spot at 7-11 and it was bad enough that the guy in the car next to me had a funny look on his face. Zero noise in a straight line. So thats why I suspected a Diff problem.

I pulled the Diff out last night and took some pics. Thought it was supposed to be a VLSD, but its not like any VSLD I've ever seen. Maybe some one can help me identify it.

Some silver stuck to the magnet, but nothing serious.
http://i76.photobucket.com/albums/j11/yesd0g/Project%20240/DSCN3796.jpg

http://i76.photobucket.com/albums/j11/yesd0g/Project%20240/DSCN3794.jpg

http://i76.photobucket.com/albums/j11/yesd0g/Project%20240/DSCN3795.jpg

No markings that I could find.
http://i76.photobucket.com/albums/j11/yesd0g/Project%20240/DSCN3797.jpg

http://i76.photobucket.com/albums/j11/yesd0g/Project%20240/DSCN3798.jpg

http://i76.photobucket.com/albums/j11/yesd0g/Project%20240/DSCN3799.jpg]

[racepar1]

looks like a clutch type diff, which can be noisy. You can see the ramps on the spider gear shaft, looks like 1.5 way. I could be wrong though, I haven't seen a lot of diffs before.

[RPS1392]

So let me ask a question about the differences in oil then. In thinking I had a VLSD instead of a Clutch type LSD. Would straight 80-90 in the rear end cause extreme chatter or noise from the Diff?

[Vernal]

vlsd is a viscous clutch type system. it uses clutches to lock it up so it will give power. one question is did you put the lsd clutch additive in when you changed the oil. the additive allows the clutches to slip so you dont fry them. if you did then i would look for other problems, but i think it might be that.

[racepar1]

So let me ask a question about the differences in oil then. In thinking I had a VLSD instead of a Clutch type LSD. Would straight 80-90 in the rear end cause extreme chatter or noise from the Diff?

Yes the wrong fluid will cause the diff to make noise and act funny. Did this start right after you changed the fluid?

[RPS1392]

Yes the wrong fluid will cause the diff to make noise and act funny. Did this start right after you changed the fluid?

This is the first time driving the car with this rearend in it. I didnt do it before, but it had the stock open Diff.

[Vernal]

you need the lsd additive. if you didnt put it in hopefully you didnt fry the clutches. just put it back it, put some 80W-90 gl-5 rated gear oil and put a full bottle of the lsd additive and you're good to go.

[racepar1]

You don't need a LSD additive in a VLSD. In a VLSD the clutches and VLSD fluid are in a sealed unit separated from the actual gear oil. That diff looks like an aftermarket clutch type diff (kaaz, cusco, nismo, etc...), which needs special fluid.

[deuceforty]

You don't need a LSD additive in a VLSD. In a VLSD the clutches and VLSD fluid are in a sealed unit separated from the actual gear oil. That diff looks like an aftermarket clutch type diff (kaaz, cusco, nismo, etc...), which needs special fluid.


this is correct, ill cite some sources

Dennis , a Nissan tech that now works for a Porsche race team said ,

Quote:
A vlsd is sealed , so it uses regular stuff. You need the lsd additive for clutch type , not a vlsd.The vlsd coupler is sealed from the fluid. the gear oil is just for the pinion ring and such.

Matt Martin said ,

Quote:
VLSD's are self contained , so theres no need for lsd additive. The clutches the vlsd use are contained in an unserviceable "container". So whatever you put in cant reach the clutches.


a vlsd has a completely sealed unit (circled)
http://img.photobucket.com/albums/v421/slappythehomelessclown/my%20240sx/VLSD.jpg



if you have a clutch type, and you DIDNT add any LSD additive, then that could very well be your problem... if you have a dealership nearby that will probably be your best bet.

however if this doesnt fix your problems your clutch disks are likely fried

[swayray]

could it also be your axles? have you replaced your wheel bearings too?

[racepar1]

could it also be your axles? have you replaced your wheel bearings too?

Axles rarely go bad on 240's and wheelbearings don't clunk or pop, they make a grinding noise that increases with speed and load on that particular wheel.

[RPS1392]

OK, so heres the update. I got some LSD additive, put everything back together and got it back in the car. I reused the same 80-90 that was in it before (only had 25 miles or so on it) + additive. I drove the dame distance I did yesterday, and there was some improvment. The rear end still chatters some on sharp turns, but not nearly as bad as yesterday. Too bad I didnt know up front that it was'nt a VLSD. Could have saved me a lot of headaches. So now I have to figure out what brand it is. like I said earlier. I did not find any external markings.

[Timeattack]

this is correct, ill cite some sources

Dennis , a Nissan tech that now works for a Porsche race team said ,

Quote:
A vlsd is sealed , so it uses regular stuff. You need the lsd additive for clutch type , not a vlsd.The vlsd coupler is sealed from the fluid. the gear oil is just for the pinion ring and such.

Matt Martin said ,

Quote:
VLSD's are self contained , so theres no need for lsd additive. The clutches the vlsd use are contained in an unserviceable "container". So whatever you put in cant reach the clutches.


a vlsd has a completely sealed unit (circled)
http://img.photobucket.com/albums/v421/slappythehomelessclown/my%20240sx/VLSD.jpg



if you have a clutch type, and you DIDNT add any LSD additive, then that could very well be your problem... if you have a dealership nearby that will probably be your best bet.

however if this doesnt fix your problems your clutch disks are likely fried


how about just put additive in it anyway cause its cheap and only helps

[deuceforty]

how about just put additive in it anyway cause its cheap and only helps


do you know how a viscous LSD works?

i THINK this is correct, if im wrong you guys can just slap me with negative rep for being a retard, but this is how i learned it

in an LSD, be it viscous or not, there are floating disks that have a silicone based fluid, in a VLSD, these disks and silicone fluid are in a sealed section in the middle of the diff (see the FSM picture), when that fluid heats up, the silicone expands and causes the plates to lock, which locks up the diff. this is why LSD additive must be added to the clutch type diffs, so that the plates can lock and everything mesh correctly

edit: im not saying not to put the additive in, just saying if its really clunking that bad there is obviously something wrong back there.

[racepar1]

OK, so heres the update. I got some LSD additive, put everything back together and got it back in the car. I reused the same 80-90 that was in it before (only had 25 miles or so on it) + additive. I drove the dame distance I did yesterday, and there was some improvment. The rear end still chatters some on sharp turns, but not nearly as bad as yesterday. Too bad I didnt know up front that it was'nt a VLSD. Could have saved me a lot of headaches. So now I have to figure out what brand it is. like I said earlier. I did not find any external markings.

Clutch type diffs are known to clunk and pop. I really wish some guys with more experience with diffs would post their opinions though. Post the pics you have in the identify this thread somebody should know what brand it is and then you can buy the 100% correct fluid that the manufacturer reccomends. If you still have your old open diff I would reccomend that you run that untill you can identify the LSD that you have and put the 100% correct fluid as you can damage the clutches.

[RPS1392]

Ok, done some research, and am convinced that the clutch packs are being a bit grabby. I've replaced the oil with redline 80w90, and added friction modifier. But nothing has changed. Going around corners under power, the Diff chatters, like its grabbing, then letting loose. Anyone with some experience in clutch type LSD throwing in there opinions would be great!

[devnull]

do you know how a viscous LSD works?

i THINK this is correct, if im wrong you guys can just slap me with negative rep for being a retard, but this is how i learned it

in an LSD, be it viscous or not, there are floating disks that have a silicone based fluid, in a VLSD, these disks and silicone fluid are in a sealed section in the middle of the diff (see the FSM picture), when that fluid heats up, the silicone expands and causes the plates to lock, which locks up the diff. this is why LSD additive must be added to the clutch type diffs, so that the plates can lock and everything mesh correctly

edit: im not saying not to put the additive in, just saying if its really clunking that bad there is obviously something wrong back there.

The way you explained above is correct for VLSDs.

Clutch LSDs rely on mechanical leverage created by driveline torque acting on the internals to engage the clutches and lock the diff.

[SoguRacing]

i have a 2 ways lsd. not sure which brand. it always clunks when i turn while in gear during accel or decel. its been doing this for 3 years since i got it. its normal for older sytle diffs to make that sound. by the way, i get funny looks too sometimes

[RPS1392]

i have a 2 ways lsd. not sure which brand. it always clunks when i turn while in gear during accel or decel. its been doing this for 3 years since i got it. its normal for older sytle diffs to make that sound. by the way, i get funny looks too sometimes

Like...clunk clunk clunk clunk in succession? Im paranoid as it is my daily.

[ryan hagen]

clutch types chatter when you turn, especailly if a "drifter" packed it tight. every one i rode in that had a clutch type and was ment for drifting chatters when you turn. good score way better than a vlsd.

[SoguRacing]

yes, clunk clunk clunk. loud and sounds like its broken from the outside. i've taken it to the mechanic for other things and they drive it and say it sounds like something is broken lol. what do they know..

[suprmods]

sounds like you have a 2 way lsd my friend. clunks under sharp turns. lsd additive can help the noise slightly, but basically all 2 older 2 ways will clunk. kaaz and a few other companies are starting to come out with quieter 2 way LSDs.

[Flaco S14]

I had a 2way on my old car and yes it clunks when turning. every car i have ridden in with a 2way clunks, in my opinion you defianately have a 2way.

[Jonnie Fraz]

Way to go! Sounds like you scored big time! I agree that it sounds like a two way. Looks allot like my Cusco. Clunking and chatter are normal to an extent. Running the correct fluid will help. I am running Motul 90pa.
If it starts clunking just give it some gas and the clunk will change into the squeel of tires...Much better!

[Mr. Jesse]

same thing happened to me. bought a vlsd from a warehouse, ended up being a clutch type (yay) makes a shit load of noise but it locks up good. just use some good oil (mobil 1) and the lsd additive, hopefully the severe clunking gets better. mine never did though.

[BrioFett]

i have a nismo 2way, it clunks on slow turns, it's normal

[wangan_cruiser]

i have clunks too. when i try to accel then i shift i hear "clunk" then shift again "clunk". but when i turn no "clunk" instead itll grab quick. FUCK i wonder if i got one of those clutch type. i cant tell. oh and my rear end came off from an r32