Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum - View Single Post - S14 Continuous clunking/knocking coming from rear only on acceleration/load

keeeban · 03-13-2013, 09:09 PM

Noise seems to be coming from the rear driver's side and also felt under the driver's seat. Sounds like something constantly hitting or rattling another thing only under load
This only started happening right after swapping the rear subframe bushings for energy suspension polyurethanes, and swapping the drivers side rear axle for a good used one. Had never heard this kind of noise before. Car has a vlsd as well.

This noise does not appear when off the gas, or in neutral; only when on the gas. Sound is slower at lower speeds, but the sound speeds up if I put the gas pedal to the floor. More apparent at lower rpms, sound gets faster and louder when gas pedal gets mashed to the floor. At higher rpms in 1st and 2nd gear, sound is less apparent and seems to go away. No sound upon braking, or coming to a stop. ONLY when on the gas, the sound appears. Since it sounds like a rotating sound the only things I can think of are the hub, wheel bearing, axle, diff, or driveshaft. But before swapping the subframe bushings and drivers side axle, things were fine.

After some diagnosing, rear driver's side RUCA heim joint is worn, and causes the wheel to have play by pulling when the car is jacked up, which could also be the wheel bearing/hub, or both, but it's hard to pinpoint this clunking noise only coming from a bad heim joint/wheel bearing, but I guess it may be possible due to the rear squatting and causing stress to the joint? Will definitely be replacing the cheapo godspeed rucas asap, but would like any input on what else this noise can result from.

Axles are all bolted up tight, driveshaft seems fine, and no excessive play in the axle shafts & driveshaft. This noise only appeared after changing the subframe bushings and the rear driver's side axle.

Will be swapping the differential bushings as soon as midterms are over next week since those are definitely worn as well.

Hopefully, the noise is just coming from the diff bushings as 'aznpoopy' had a similar problem in his thread back in 06:

http://zilvia.net/f/tech-talk/112116-rear-clunking-under-load.html

I was going to PM him to see if this is the same noise he had, but he hasn't been on since 2011, so i'm making this thread to get more input from the more experienced members.

Thanks in advance for any help

03-13-2013, 09:09 PM	#1
keeeban Zilvia Addict Join Date: Apr 2010 Location: Bay Area, CA Age: 31 Posts: 924 Trader Rating: (22)	*S14 Continuous clunking/knocking coming from rear only on acceleration/load - video** Noise seems to be coming from the rear driver's side and also felt under the driver's seat. Sounds like something constantly hitting or rattling another thing only under load This only started happening right after swapping the rear subframe bushings for energy suspension polyurethanes, and swapping the drivers side rear axle for a good used one. Had never heard this kind of noise before. Car has a vlsd as well. This noise does not appear when off the gas, or in neutral; only when on the gas. Sound is slower at lower speeds, but the sound speeds up if I put the gas pedal to the floor. More apparent at lower rpms, sound gets faster and louder when gas pedal gets mashed to the floor. At higher rpms in 1st and 2nd gear, sound is less apparent and seems to go away. No sound upon braking, or coming to a stop. ONLY when on the gas, the sound appears. Since it sounds like a rotating sound the only things I can think of are the hub, wheel bearing, axle, diff, or driveshaft. But before swapping the subframe bushings and drivers side axle, things were fine. After some diagnosing, rear driver's side RUCA heim joint is worn, and causes the wheel to have play by pulling when the car is jacked up, which could also be the wheel bearing/hub, or both, but it's hard to pinpoint this clunking noise only coming from a bad heim joint/wheel bearing, but I guess it may be possible due to the rear squatting and causing stress to the joint? Will definitely be replacing the cheapo godspeed rucas asap, but would like any input on what else this noise can result from. Axles are all bolted up tight, driveshaft seems fine, and no excessive play in the axle shafts & driveshaft. This noise only appeared after changing the subframe bushings and the rear driver's side axle. Will be swapping the differential bushings as soon as midterms are over next week since those are definitely worn as well. Hopefully, the noise is just coming from the diff bushings as 'aznpoopy' had a similar problem in his thread back in 06: http://zilvia.net/f/tech-talk/112116-rear-clunking-under-load.html I was going to PM him to see if this is the same noise he had, but he hasn't been on since 2011, so i'm making this thread to get more input from the more experienced members. Thanks in advance for any help __________________ Last edited by keeeban; 03-14-2013 at 12:58 PM..