tannji Posted July 21, 2003 Share Posted July 21, 2003 Hey all... I have what sounds and feels like a rear end clunk, when I put the car into gear, or reverse. My ECM failed this weekend, so I took the opportunity to check out the situation underneath while it was in the shop. I was expecting to see worn mustache bar or diff mount bushing, and/or half-shafts. Imagine my surprise when the shafts all appear to be tight, and the bushings in the diff mount and mustache bar appear brand new!! so, what gives? (pun not intentional) I am running the 700r tranny and wondered if this is likely to be a tranny problem that is transfering its impact to the rear thru the drive train? or is there something a little more specific to look for in the rear drive train? thanks, tannji Quote Link to comment Share on other sites More sharing options...
tannji Posted July 21, 2003 Author Share Posted July 21, 2003 While I am at it.... I would like a limited slip rear... Of course, lol. I have the opportunity to pick up a 91 240sx, 5sp with the 2.4 motor. does anyone know the specs on the rear, and whether or not I will want the brake system off this for a disk conversion on my 240Z? Is there a online reference source that will spec out the probable parts in that 240SX, and do I need the VIN # or all the build numbers on the car? I can pick it up in mechanically good shape for $300, as it has a seriously challenged Title.... I noticed that the diff to the naked eye looks like a R200, and has the finned rear cover... thanks again, tannji Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted July 21, 2003 Share Posted July 21, 2003 The front diff mount can be torn, but appear OK when at rest. Have you checked the shock towers and the control arm bushings for looseness? Quote Link to comment Share on other sites More sharing options...
tannji Posted July 21, 2003 Author Share Posted July 21, 2003 Thanks for the reply! I looked at the front mount while the car was in the air, lifted by body jack points.... suspension was unloaded. the tear would still be likely to be compressed and not visible? The only time I have seen them torn it was so blatantly obvious that there was no question.... this time, I am not sure... Also, what am I checking in the strut tower? spring sloppiness, ect? or what specifically. The control arms I think were good, will double check tho. Front end of the car is a different story, everything I quickly glanced at needs new bushings.... the strange thing is... handling and steering wheel responsiveness is not too bad..... but it has been about 12 years since I have felt a tight or competitive Z, so perhaps I will be startled when I replace all that. tannji Quote Link to comment Share on other sites More sharing options...
j260z Posted July 21, 2003 Share Posted July 21, 2003 you should also check the diff strap (if you still have one). Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted July 21, 2003 Share Posted July 21, 2003 Thanks for the reply! I looked at the front mount while the car was in the air' date=' lifted by body jack points.... suspension was unloaded. the tear would still be likely to be compressed and not visible? The only time I have seen them torn it was so blatantly obvious that there was no question.... this time, I am not sure... Also, what am I checking in the strut tower? spring sloppiness, ect? or what specifically. The control arms I think were good, will double check tho. Front end of the car is a different story, everything I quickly glanced at needs new bushings.... the strange thing is... handling and steering wheel responsiveness is not too bad..... but it has been about 12 years since I have felt a tight or competitive Z, so perhaps I will be startled when I replace all that. tannji[/quote'] Just check for loose fasteners and such. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted July 22, 2003 Share Posted July 22, 2003 Just retorque all the bolts. Don'f forget the bolts holding the bar to the back of the diff. With the car in the air you need to lift up on the front of the diff to see the broken mount. Also try retorquing the nut on the top of the strut shaft. If those get loose, they can gouge out the D shaped hole in the strut isolator. Eventually the clunking around will wear through the strut shaft. Ask me how I know. Quote Link to comment Share on other sites More sharing options...
tannji Posted July 22, 2003 Author Share Posted July 22, 2003 that "D" shaped hole seems to ring a bell with me as well..... details are starting to filter back to me from way back when I was driving these things... its been about 12 years, and I dont seem to "know" as much as I used to... = ) I am really looking forward to getting this car back on a lift and sorting it out. If memory servers, this euphoric feeling wont last much past the point where I start getting dirty, so I intend to enjoy the feeling while I can. tannji Quote Link to comment Share on other sites More sharing options...
Guest billy383Z Posted July 27, 2003 Share Posted July 27, 2003 This might sound silly, but did you check the U-joints in your drive shaft while you were under your car? A friend of mine had a "mysterious rear end clunk" that in fact, wasn't. His driveshaft U-joints had some serious slop in them. After changing them out for some fresh ones, the clunk disappeared. My '77 280z has a slight clunk, but I believe that is caused by some back-lash in the ring and pinion. Also once experienced another "rear end clunk" once that wasn't- the nut/washer/rear bushing from the TC rod in the FRONT suspension of the car went AWOL and the TC rod was rattling around in it's hole in the frame and making a clunking noise that damn sure sounded like it was coming from the back of the car. Weird thing was that the car handled perfectly fine- never knew it was missing until I went under the car to do an oil change. Just a couple more things you might want to check out. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.