Guest 70datsun240 Posted October 14, 2005 Share Posted October 14, 2005 ok, Ive tryed everything to pin point the noises coming from my rear end. while slowly moving forward or reverse there is a du-dunk clunk noise and feeling, more so from the passengers side rear. it feels like the whole suspension unit is moving forward and back slightly. I was under the car for hours and all the bushings look old and cracked. I tightend up all the bolts i could see and it still does. Oh yea, I have a load bang noise near redline in first gear too. I read it might be because the from of the diff is "nosing up" and hitting the floor. But mu diff strap looked in tackt. I tryed prying it to see if there was excesive movement and the rear of the diff moved up and to the back more so that any movement from the front. I jacked one tyre up and rotated the tire, seemed fine. But when i shook it front to back there was movement between the tyre the halfshafts. what would this be? I rotated the halfshafts by thank and there was about quarter inch of movement, is this too much? But anyway, Ive becided to remove the whole rear suspension unit and diff drom the car. Im going to take it all apart clean and paint it replace whatever needs. Since im doing all this is there any tips you can give me to make this rear last for years to come? Is there any COMPLETE polly bushing sets for the rear suspension at a good price? Any tips and help would be apreciated!! Ohh yeah, and the differential on a 1984 300zx turbo, is it lsd? Thanks in advance!!! Quote Link to comment Share on other sites More sharing options...
Sleeper-Z Posted October 15, 2005 Share Posted October 15, 2005 ok' date=' Ive tryed everything to pin point the noises coming from my rear end. while slowly moving forward or reverse there is a du-dunk clunk noise and feeling, more so from the passengers side rear. it feels like the whole suspension unit is moving forward and back slightly. I was under the car for hours and all the bushings look old and cracked. I tightend up all the bolts i could see and it still does. Oh yea, I have a load bang noise near redline in first gear too. I read it might be because the from of the diff is "nosing up" and hitting the floor. But mu diff strap looked in tackt. I tryed prying it to see if there was excesive movement and the rear of the diff moved up and to the back more so that any movement from the front. I jacked one tyre up and rotated the tire, seemed fine. But when i shook it front to back there was movement between the tyre the halfshafts. what would this be? I rotated the halfshafts by thank and there was about quarter inch of movement, is this too much? But anyway, Ive becided to remove the whole rear suspension unit and diff drom the car. Im going to take it all apart clean and paint it replace whatever needs. Since im doing all this is there any tips you can give me to make this rear last for years to come? Is there any COMPLETE polly bushing sets for the rear suspension at a good price? Any tips and help would be apreciated!! Ohh yeah, and the differential on a 1984 300zx turbo, is it lsd? Thanks in advance!!![/quote'] it looks like you already pinpointed your problems... bushings and movement. movement may come from the wheel bearing or associated parts. bushings are a definate must, you should also check the mounts and make sure those are all fine. you could solid mount your diff so you won't have to worry about bushings. did a quick search on google and found these urethane bushings... http://www.courtesyparts.com/energysuspension/oldzcar.html also found this: http://www.z31.com/history.shtml it seems turbo models from 4/87 came standard with LSD. just take it step-by-step. don't give up! if you do, give me your vin plates and title! J/K. cheers, steven m. Quote Link to comment Share on other sites More sharing options...
HizAndHerz Posted October 15, 2005 Share Posted October 15, 2005 When I first got my 1978 280z, it had the notorious rearend clunk. The PO had cut up old tires and used them as bushings. Scary. However, after a full Energy Suspension poly bushing set, it still had the clunk. Then I replaced the u-joints on the stub axles since they were a bit loose. The driveshaft had already been fixed by the PO. Still had the clunk. Then I found that the long bolts that hold the front differential mount in place had backed out about 1/8" and were stripped. After replacing the bolts and the differential mount, guess what? It still has the clunk. I've checked the bearings and spindle pins. They look fine. The differential has no excess play. Most likely, it is the struts or strut mount. I'm tackling those, the wheel bearings and spindle pins next week. So, this is all just to say that there are many things that can cause the rearend clunk. I've found several problems but haven't rooted out the culprit... yet. Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted October 15, 2005 Share Posted October 15, 2005 I had the EXACT same problem...after lookin and looking I finally grabbed the axle and twisted and sure enough is went klunk...I thought my whole rear suspension was falling apart or the control arm bushings were gone but it was the u-joints...$40 fix... Quote Link to comment Share on other sites More sharing options...
Guest JAMIE T Posted October 15, 2005 Share Posted October 15, 2005 Excessive backlash in the diff will also cuase noise like that. Quote Link to comment Share on other sites More sharing options...
big-phil Posted October 18, 2005 Share Posted October 18, 2005 I have the same clunk. I now got new bushings, struts, and a-arms! and guess what...................still goes clunk! when starting off (sorta hard, like poping the clutch). I think it is the rear end hitting the floor???? Quote Link to comment Share on other sites More sharing options...
Guest 70datsun240 Posted October 18, 2005 Share Posted October 18, 2005 One more question, when I move the rear tires left and right, they move alot in my opinion. Its happining between the wheel and halfshaft. I dont know what the proper word for that peice is, Ill just call it the thingy with the wheel studs on it. Anyway, what would be worn out here? wheel bearings? Nut not tight enough? Can someone help so I know how to find out or what to get to fix this, thanks. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted October 18, 2005 Share Posted October 18, 2005 They are called stub axles. And there are wheel bearings in there which could go bad or get excessive slop in them. If you have a 1970 240 like your screen name implies, then you also have the smaller stub axles. They have been know to snap. When they do, if you still have stock drum brakes, then there will be nothing holding your wheel on the car. It would probably not be a bad idea to pull the 35 year old stub axles out and inspect them anyway. You could then easily upgrade them with the heavier stubs out of a 280. Keep in mind that replacing stub axles is not alway easy. Do a quick search to get some details. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted October 18, 2005 Share Posted October 18, 2005 The splines on the stub axle and companion flange wear, and this causes play like you're describing. Replace the one side at least. You should also replace the bearings and seal in there since they're not easy to get to. Pop gives good advice, search about the stub axle removal. Especially the nut. Gotta take that nut off the right way or else you've made a whole lot more work for yourself. Quote Link to comment Share on other sites More sharing options...
HizAndHerz Posted October 19, 2005 Share Posted October 19, 2005 I have the same clunk. I now got new bushings, struts, and a-arms! and guess what...................still goes clunk! when starting off (sorta hard, like poping the clutch). I think it is the rear end hitting the floor????Sounds like you're in the same boat as I am. Have you checked the front diffy mount and the long bolts that secure it? How much play is there when you try to rotate the drive shaft and stub axles? Mine is not really a 'clunk' but more like a 'BLAM!'. I've got a spare R200. I'll probably change the seals and put it in along with yet another new front mount. I hope you find out what's going on with yours. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted October 19, 2005 Share Posted October 19, 2005 I have the same clunk. I now got new bushings, struts, and a-arms! and guess what...................still goes clunk! when starting off (sorta hard, like poping the clutch). I think it is the rear end hitting the floor???? It is possible for the diff to hit the floor. When the strap goes and the front mount goes, the mustache bar is really the only other thing holding the diff down when you accelerate. It works like a spring and can actually spring enough to allow the front end to wind up and hit stuff under the car. A friend of mine with an R180 has taken out her e-brake mechanism and then the driveshaft put dents in the tranny tunnel (!) when the strap and front mount failed. Quote Link to comment Share on other sites More sharing options...
ZR8ED Posted October 19, 2005 Share Posted October 19, 2005 Jon. That happend to me. Stock mount, no diff strap. VG30ET pushing 9 psi on a hard launch on the drag strip. The diff mount broke, lifted up, hit the tranny tunnel, and ripped off my E brake parts in that area, and pulled on my ebrake fully on both wheels. I still managed a quarter mile time of 14.7 hehehe Scott Quote Link to comment Share on other sites More sharing options...
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