clunk/thump sounds after spl bushings installed
 

i have a question/problem for all the members that has all these spl parts installed on their car..

-spl front lower impact bushing
-spl front lower arm bushing
-spl solid rear diff bushings
-spl rear subframe bushings
-spl FKS rear knuckle monoball bushing set

so i have all these spl bushings installed recently.. and now i have this clunking/thump sound from the rear section.. i never heard these sound before the install.. and yes i know to expect tons of vibrations, squeaking, whining, more chatter from the clutch, etc...but i dont think this is normal..

the clucking/thumping sound happens when i engage the clutch AND release it (usually 1st and 2nd gear.. sometimes 3rd)... it also happens and sounds much louder and rapidly during wheel hop in the rain (i did it on purpose in a empty parking lot to see if that will trigger the clunking/thumping sound ) .. again.. all these sounds comes from the rear section of the car.. and u can feel it when its makes the sound..

dont know if this helps but for the spl sub frame bushing.. i told my mechanic that i want it to be oem spec which on the instruction, it listed 1 big and 1 small shim for the front and no shims for the rear...
but my mechanic told me that they tried that but without the extra shim in the rear.. the subframe will not have contact with the chassie and will leave a gap..
i dont think the sound is caused by the control arm and knuckle bushings..

any help will be appreciated.. i am putting my car on the lift tomorrow to see if everything was tightened up.. and maybe even change the trans and diff fluid..

Just curious you have a 2013 Z why change all the bushings?

You planning to transform your Z to a track car?

I heard the solid diff bushing will cause some of this vibration and clucking sound.

Man with all that suspension upgrade I can feel your Z is solid as a rock and you feel every little bumps?

this is not my daily car.. slowly trying to turn it to a fun track car..
i do expect all these bushings to make unnormal sounds but this just doesnt feel or sound normal to me..

with all these bushings.. its actually not bad at all.. the car still on stock nismo suspension and i dont feel it much harsher driving after the install.. but i can tell u i can hear alot of different sounds from squeaking noise to whining sounds lol

Let as know what you find out what's causing this abnormal sounds. Maybe it needs more drive miles to make everything settle in.

I'm considering of changing my transmission mounts but I would use the Z1 polyurethane one.

For one there's are a lot of plastics/ foams, heat shields that vibrate in the trunk after I switched to coilovers, had to use dynamat to cover all my trunk, heat shield, license plate bracket, stuffed the rear bumper foams with rug towels from vibrating, reinforce my exhaust hangers and bushing.

The price we pay for upgrading our suspension system.:icon17:

But the car handles so good on the twisties. :driving:

i will update this page as what i tried or did to fix this problem..
i have a pair of whiteline poly diff bushings at home but then after i purchase all the other spl solid bushing and motor/trans mounts.. i might as well go all out right? haha so i ended up with the spl solid diff bushings ..
dam and thats just from coilovers? i cant wait to put mine on!

yea i no know lol functional parts aint cheap .. u should see the labor on these bushings.. it cost more than the parts itself lol

I have whitelines sways bars too.. You said it right labor cost is a killer that is why I invested the money instead in buying quality tools little by little and do the job myself or ask fellow members to help for a cost of a pizza and beer!:tup:

IMO suspension upgrades and quality tires are worth the investment rather than doing any engine hp gains. Your in the right direction If you do plan to track your Z.

Sounds normal for solid mounts. That is why I will stay away form them on a street car. Been there, done that before.

i mean i dont mind any of the weird sounds and vibrations as long as its normal.. i just dont want to ignore it incase it is a problem and will damage other parts that will cost me thats all

I have replaced pretty much all my suspension with spl bushing, the diff bushing is Whiteline. I have not done the sub frame bushings though. I had some clucking when going over ruts and bumps in the road. Tony at Fast Intentions checked it out for me while my car was at his shop before ZDayZ. He couldn't find anything wrong so I thought okay one more sound to the other 101 sounds associated with the car. Then I went to ZDayZ and drove the car like I stole it and now I have no more clunking. It may need to be whipped and spurred to get things to settle. I love the upgraded suspension, stock Nismo is not bad at all, but now the suspension is definitely better than its driver.:)

thanks for letting me know! i will drive it like i stole it after i check with my mechanic and inspect everything..
i just did alot of research within the past few hrs and im thinking its either something to do with the driveshaft, differencial, or sub frame bushing spacers.. will update yall in a bit.. heading there now

so i just got my diff and trans fluid flush with red line fluids.. still makes the sounds.. putted the car back on the lift and and started the car and did 1st - 3rd 2500-3500k slow shifts and the sound seems to be coming from between the driveshaft and the transmission... hmm no clue whats wrong at this point.. when they were under the car they said it makes the sound when clutch engages when the shaft stops and go.. also got the solid z1 motor mounts installed and dont no if that have anything to do with it either...

Attachment 105719

its the area that i circled in red that makes the clunk sound

Sounds like the driveshaft may be binding, if the subframe changed height that could have caused it.


The DS input could be hitting the tailshaft under load. Look for marks on either.

My car has been clunky since I got my hp upgrade. It is very noticeable when I leave her in fist, step on the gas then let go. It clunk hard when the drive train is loaded then quickly unloaded. I have stock nismo suspension other than urathane motor mounts and rear diff. The clunk does not feel right to me either.

YzGyz

WOW you went full retard on sound dentoning. I don't notice it until my wife tells me its annoying. But I would rather maintain the weight of my car and deal with the noise than put all that extra weight in.



For OP I sent you a PM back. From what I can tell its possibly the tranny mounts or sub-frame bushings. But now seeing what you have the only other possibility is the tranny mounts. Other manufactures use a bushing in between the tranny and the drive shaft that when torn makes a clunk sound but ours do not have that. So by process of elimination the only to spots are the motor mounts and tranny and you have the motor mounts too. But before you spend more dough, take it into a speed shop and see if their tech has any recommendations. Because to make that clunk noise it has to be a big heavy component between something malleable and a relatively large change. A smaller component with little play would make a rattle noise, vibration.

Is it possible the lock nut on your rear coil over came a little loose?