Hey everyone. I finally got around to rebuilding and installing the posi rear end I bought for my 69 Electra. Set all the bearing preloads and backlash exactly to the factory manual spec. The reason I rebuilt it was my findings of heavily pitted bearings inside the housing that would've made a hellish sound had I tried to run them. Anyway, after installing the rear I'm getting a whining sound. This only happens under VERY light maintenance throttle. Coasting and deceleration it's silent. Under normal acceleration its near if not silent (can't really tell over the sound of the side pipes). It's only happening under the extremely light throttle. This is my first rear end rebuild but I had an experienced family member who's rebuild 100's of rears there helping me set it up and check the specs. I really think it's all set properly. I'm wondering if it could be the gearset making the noise. Perhaps the used gearset is just not in its old wear pattern anymore? As you all know, the 9 3/8 has no aftermarket gearsets so re-using the old one was really my only choice. It didn't seem pitted or damaged like the bearings were so I figured it would be fine. I've put maybe 30 miles on it so far. Should I just keep taking it easy and see if it goes away? Am I screwed because of the old used gears and they' ll just make noise for eternity? Is the noise related somehow to the posi carrier? Let me know what you all think about the situation. Thanks so much for your help.
Posi will not make the noise...You can put that one to bed. Gears in a floating stat can make pitch change when a slight contact to coast or drive side can be the pinion depth if just very close and not enough one way or the other. Also obviously we can not see the pattern your used gears gave... We do not know what backlash your running Pinion depth thickness you used Can not feel the preload of your carrier and or pinion either. SO ....We are not going to be much help here. Trial and error on used gears . NOT what you wanted to here BUT that is it. On used gears you need to find where those gears road in another rear. If you just bought them and were not able to get backlash from the housing they were removed from it could be detrimental to the re install in another housing and know if they could have been loose in another housing causing a weird anomaly pattern causing the issuer your having. Jim JD Race
