Please help

https://www.youtube.com/watch?v=4LbXFMd4lqk&feature=youtu.be

 

Seems to only happen under acceleration. What have you checked so far? Mods?

 

Happens wen cruising as well strange s60 rear aftermarket upper and lower control arms. Tq arm and torsion bar

 

The first thing I'd start with is jacking it up and start wiggling suspension parts and each rear wheel by hand to see if anything is loose. The knocking is hopefully from that.

After eliminating the easy/cheap fixes, I'd have a shop look at your rear end.

 

Jack up the rear end and run it on the stands, if it makes the noise, it is the rear. If not then it is the suspension. Check for any bushings that might be completely shot, does it seem to have a rhythm or does it happen more over bumps?

 

https://ls1tech.com/forums/suspensio...ing-sound.html

This sound like your problem?

 

The rhythm gets faster but not necessarily louder as I go faster

 

I would give advice, but I have not the slightest clue to what in the world is creating that noise. My idea is that it isn't the suspension, if that gets you anywhere I don't know, it still could be though. It's almost as if someone zip-tied your driveshaft with a soft zip-tie..dang I'm clueless on this one.

Does it go away when you apply the brakes at all? I'm very interested in this because the noise sounds very linear as you drive but it's not a squeak or squeal like you'd get from metal contact.. Keep this updated I wanna know!