S14 Rear End Vibration - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

DaMidNiteBeast · 01-12-2018, 09:49 AM

Hey everyone,

I recently installed some PBM coilovers on my S14 and noticed an obvious vibration from the rear.

More info: Just pushing the car by hand (pushing forward, pushing backwards does not cause the vibration) will cause the entire rear end to shake. the vibration is generated from the rear, and will shake the whole car. When I jack up the car using the Diff, 1-2 inches off of the ground, I am unable to move the tires by hand. However, if I jack up the car up more as if to do work under it, the tires are able to rotate much more easily.

My question is, what is causing this vibration to suddenly disappear once I raise the car up? (Only occurs when pushing forward on the ground, will not vibrate when going in reverse) I tried raising the coilovers but they are almost maxed out in height. The car did not do this (from what I recall) with the stock suspension. I gave it a drive around the neighborhood and I noticed it will only vibrate when coming to a complete stop moving forward. Steering wheel doesn't shake and transmission doesn't shake.

I highly doubt it's the e-brake cable, but I'll loosen it up a bit and see what it does.
Drive shaft on it's way out/already out?
Axle binding from being low?
Some sort of bushing is blown? (doesn't make sense due to the vibration not occurring in reverse)

Only 'mods' are welded diff, pbm coilovers, and all mounts/bolts are tight.

Other than that, is this some sort of axle binding symptoms?

Any help is much appreciated.

ZenkiKid · 01-12-2018, 11:11 AM

Really really bad subframe bushings im assuming...

DaMidNiteBeast · 01-14-2018, 09:22 PM

Ya I'll go ahead and check them out. I'm 99% certain it's my alignment.

01-12-2018, 09:49 AM	#1
DaMidNiteBeast Join Date: Oct 2017 Location: Charlotte, NC Age: 27 Posts: 6 Trader Rating: (0) Feedback Score: 0 reviews	S14 Rear End Vibration Hey everyone, I recently installed some PBM coilovers on my S14 and noticed an obvious vibration from the rear. More info: Just pushing the car by hand (pushing forward, pushing backwards does not cause the vibration) will cause the entire rear end to shake. the vibration is generated from the rear, and will shake the whole car. When I jack up the car using the Diff, 1-2 inches off of the ground, I am unable to move the tires by hand. However, if I jack up the car up more as if to do work under it, the tires are able to rotate much more easily. My question is, what is causing this vibration to suddenly disappear once I raise the car up? (Only occurs when pushing forward on the ground, will not vibrate when going in reverse) I tried raising the coilovers but they are almost maxed out in height. The car did not do this (from what I recall) with the stock suspension. I gave it a drive around the neighborhood and I noticed it will only vibrate when coming to a complete stop moving forward. Steering wheel doesn't shake and transmission doesn't shake. I highly doubt it's the e-brake cable, but I'll loosen it up a bit and see what it does. Drive shaft on it's way out/already out? Axle binding from being low? Some sort of bushing is blown? (doesn't make sense due to the vibration not occurring in reverse) Only 'mods' are welded diff, pbm coilovers, and all mounts/bolts are tight. Other than that, is this some sort of axle binding symptoms? Any help is much appreciated.

01-12-2018, 11:11 AM	#2
ZenkiKid Post Whore! Join Date: Nov 2005 Location: Nowhere Age: 34 Posts: 3,284 Trader Rating: (9) Feedback Score: 9 reviews	Really really bad subframe bushings im assuming... __________________ http://www.nissanroadracing.com/

01-14-2018, 09:22 PM	#3
DaMidNiteBeast Join Date: Oct 2017 Location: Charlotte, NC Age: 27 Posts: 6 Trader Rating: (0) Feedback Score: 0 reviews	Ya I'll go ahead and check them out. I'm 99% certain it's my alignment.