Rear Diff is Clunking, When shifting or letting of gas fast?

[uvamosk]

Here is my setup,1pcs ALUM drive Shaft300zx N/A VLSDJ30 AxelsAGX Kyb ShocksTien S tech springsK-Sport camber arms

PROBLEM:When I take off in first and I let the clutch go kinda fast you can hear a Clunk/Thud in the rear end sounds like the diff or something is jumping up.

When I shift into second same problem... just not as loud.

If I am in gear and I give it gas then let off it really fast kinda blip the throttal in gear, it will cluck/thud like the 2 examples above.

Trouble shooting:I slid under the car and shook the diff and it doesnt seem to be loose pretty secure.The diff has a small leak, so I checked the fluid it is still almost level with the check plug.

Conclusion: I am kinda wondering what is going on as it didn't do this at first when I got the car that I remember.

Any suggestions or comments.

[1unar3clipse]

I got:Subframe SpacersMR street coiloverstons of stabilizing bars180sx VLSD

my car makes the same thud and clunk, I originally had an issue with the half shaft bolts snapping from shifting between the two flanges.but since I've replaced everything with good grade material but I still get the clunk which I attribute to the VLSD+subframe spacers but IIRC there is some bushing on the drive shaft that is bad from wear and tear and supposedly this causes the clunking.I'm not sure so I'll wait for a more veteran nico-member to clear this up..hopefully slappy, yokota, or themadscientist will know the answer.

[x240xdrifter]

Completely normal, its your Ring and Pinnion Gear Backlash

being a 17+ yr old car, it might be excessive, but its nothing to be alarmed about. The only way to fix it is with new shims and a Dial gauge. If backlash becomes too much though, it can damage the gears overtime.

[1unar3clipse]

would you say its worthwhile to fix it?I'm Probably going with a Kaaz 2-way soon and If its something cheap and worthwhile I'll probably do it to quiet the chatter down.

[x240xdrifter]

its deff. worthwhile it you got the diff out and another form of transportation. Shim can be found at local auto stores if not the dealer. Its not too complicated, you just need some needle nose pliers, a dial gauge like this:

...and some shims I am sure they have detailed write ups of the process somewhere over the interweb

edit: shims are cheap too

[uvamosk]

Well, I am thinking of dropping the diff and throwing in sub frame bushings when I put my RB20det in.. that will be some time next year though.

Would there be any big issue with waiting till then? I got the diff from a 91n/a 300zx. with 140,000 miles on it.

I haven't ever had this problem with my other 4 240sx's or my Hatchi

[x240xdrifter]

ya I think you'll be fine, mines been doing for awhile now, and I've had no problems. Blacklash is normal, your supose to have alittle amount of "clunk" to it, but I believe anything over 0.005" of play is consider excessive. So if its really loud or jerks hard, chances are it is out of spec. All this is doing is putting stress on your ring and pinion gear. I suggest to driving like a granny till its fixed. Better safe then sorry right? Once you have it out, just inspect the gears for any damage

[Bronze MFP]

You might need new subframe bushings.I got subframe spacers thinking they would solve my clunking problem, and they did for about 3 months, then the clunking came back even with the spacers.When I replaced the bushings, 2 of the stock bushings had completely separated.After putting solid subframe bushings in, no more clunking. Backlash on the diff shouldnt be as harsh as a subframe clunk, its more of a bucking motion when you get on the gas quick, or let off the gas quick.

[uvamosk]

Sounds, good I'll check both then, I'm going to drop it soon anyway to fix the leak so i'll just go ahead and throw bushings in and i'll check the clearnces.. Thank you guys so much...

[uvamosk]

Well, it snowed and now I got to really feel the problem...

Most the time when I lose traction The rear end starts Shacking, studering and clanking. It shakes kinda bad. When I get traction it goes away. It almost feels like when you do a burn out and you get really bad wheel hop. I'm also kinda at a lost as I have a VLSD but the car loses traction so easy it isnt funny.

I had a AE86 GTS and It never lost traction that easy. ... Though I could just be paranoid lol its been 2 years since I have been on enough snow to tell. LOL

[scottydog]

Check the universal joints.

[uvamosk]

So you think the CV axels could be it?

I Think i'm going to order subframe bushings and spacers... I'm trying to decided if i should get axels then or not.

[JOESCHMID26]

My car has been doing the same thing since i got it a year and a half ago. heres a list of what i have done and it still does it.Nismo suspensionenergy suspension complete bushing kittanabe sway barsgreddy strut tower barsnismo subframe bushing with the poly insertspulled the diff and swapi just got a peak performance transmission mount its either that or the driveshaft support bearing is bad and i already replaced this transmission mount with the stock 1 and it didnt do muchi see no sense in replacing the support bearing it costs 90$ i believe and the u joints in this shaft r staked if the transmission mount doesnt do it im replacing the driveshaft with a dds aluminum shaft its about 450$ and it drops alot of rotating mass if anyone figures this out let me know otherwise ill post after i solve it.

[DadaG]

95 240SX I have a clunk because of slack between wheel/hub and the axle. There is play before the axle engages the wheel. Anyone had this problem and fixed it? (It is not the sub frame bushings!) It happens only with rotation. Nothing else is lose. New axles and Kaaz diff.