rear end rumble and vibration
I recently took delivery of a 1976 Spider purchased on Ebay from California and transported to Kentucky. On first drive, I discovered a rumble noise from the rear of the car and vibration that can be easily felt. It occurs when pulling from a stopped position and when accelerating thru first and second gear, mainly. It is mostly while under pressure. It becomes less noticable once you are up to speed and does not exist at all when coasting. I gave a limited check of the u-joints, carrier bearing and guibo thing. Holding one end of the drive shaft and turning the other presents no excessive play, and the rubber appears to be solid. Turning the drive shaft, it seems to move about 1/8th of a turn before taking up the slack in the rear end. Same with turning one rear wheel...about 1/8th of a turn play in rear end. I just changed the rear end oil, which did seem to make rearend a tad bit quieter, but did not affect the rumble and vibration. While on the stands and running, I put car in gear and let out clutch. No noise or vibration. The trunnion arm bushings appear to have chips out of the area between the ridge on the arm and the mounting bracket to the body. I suspect this to be the cause of the rumble and vibration. Finally, here's the question. 1) can the trunnion arm be removed and bushing replaced without taking out the rear end. 2) Would it be just as easy to remove the rear end and replace ALL bushings...I think I know the answer to that one. 3) does any of this sound like there could also be a differential issue. The car is a no rust, complete, un-molested, original car with only minor paint issues which will require minimal body work and a paint job. I plan to have the car for some time and making improvements/repairs as needed and plan to keep it pretty much original. For you Lexington,KY guys....I'm still looking for answer to who would be a good mechanic in the area to do those jobs beyond my experience level. Looking forward to a drive that doesn't sound like the rear end is coming out from under the car. This is a great forum. I spent the past several years looking at the Triumph Register forum that seemed like a ghost town. It's nice to see people being active. Thanks for your input.