Long story short, I had a clunking noise which sounded off with the rpms. If I sped up the noise would be faster, slow down, noise slow down. I thought bad u-joints. I go under the car and the driveshaft is a little loose. I look at the clamps that hold it to the rear end and the clamps are loose. Bolts were not in all the way. I try to tighten them, but they don't move either way.

I take it to a shop, they end up replacing the clamps, broke a bolt off, had to drill and retap, and put new u-joints in, and said that should take the noise away. I drive away, and the noise is still there. I'm like WTF. I just spend $150 and the noise is still there. I take it back, and explain to them the symptoms. Really only does it when your on the gas. Not in N while coasting or anything. So they put it on the lift and have it running to see where it's comming from. They call me back later on and said it's not coming from the rear end, not coming from the tranny. He said it's coming from the middle of the driveshaft. I have a 1 pc aluminum one btw. He said maybe it's doubled walled and something broke off inside. What do you guys think about this? What should I do now?

 

well, a bad tranny mount will allow the driveshaft to smack the tranny tunnel on the car and cause some nasty sound effects, however

driveshafts are tubes, and capped on both ends, a single piece of cast alluminum that diameter would... be interesting, weigh a decent amount, and be subject to flaws in the casting process that could shear the driveshaft.

it's not unheard of for the inner tube of the driveshaft to come out of whack, but for it to make noise is kinky, when i had my driveshaft shortened, they had to replace my inner tube, however, that's a steel shaft, but i can't imagine it would be cost effective to make that entire thing one piece, it would cost too much in just material.

however that's just part of my overly long post, since you had some messed up clamps, my overly technical explanation.....i'd say u joints may be missing a bearing, gear tooth got knocked off, or the transmission got messed up, my logic...

when the clamp broke, the driveshaft was rocking side to side unsecured, whatever caused this could have messed up the rear end or the transmission, or, driving it with the driveshaft messed up could mess up other stuff, the driveshaft seems to be makeing the noise in the center because it's conducting the sound waves.

or it could just be the inner tube of the driveshaft sheared or out of line? replace the driveshaft, shouldnt be too hard to find one in a junkyard or something, they were used from 82-the end if i remember correctly, however measure it to make sure, replace it and see if it keeps making noise, one thing nice about driveshafts, they come out easy

 

I guess i'm just going to have to buy a new driveshaft again. I just didn't want to have to spend another $150 for a new aluminum one and it not even be the problem. Thank you for your reply.

Shawn

 

Maybe its just out of balance....i dunno I just do what he said and get a new one, maybe a stonger one to handle future mods.