Is it possible for a clutch type LSD to create a vibration during normal, straight-line driving? I have begun to suspect my 9in. aftermarket third member (about 2 years old) as being the possible source of a vibration that I have been tracking down, one that I thought I had solved.
I was having a vibration in the chassis (not steering wheel) at 55-60 MPH, though it sometimes varied a bit. It was not tire or wheel related. I installed new u-joints, didn't solve the issue. I spun the driveshaft 180 degrees on the differential yoke, which seemed to improve slightly, but not a solution. I then installed a spare driveshaft, which seemed to solve the problem, making me suspect my original driveshaft needs balanced. However, yesterday during a drive, it seemed to momentarily return, and under some strange circumstances.
I turned left from a stop sign under normal driving throttle, whereupon initial throttle application, a little "chirp" from the rear left tire occurred, as if it had been sitting on a rock, which was spit out and caused the tire to "chirp". I state "as if", because I don't think the left rear tire was on anything but clean pavement (though I can't be 100% certain).
I drove to the next stop sign and turned right under normal throttle, which is when my vibration returned at 50-60 MPH. I instantly thought of the differential, and was able to perform a couple somewhat aggressive left and right turns from a stop, and the vibration hasn't returned as of yet.
Motor and trans mounts are good. Inspected driveline looking for issues, nothing seems out of the ordinary.
I'm wondering if it needs another bottle of friction modifier and another "break-in" period in an abandonned parking lot.
Any thoughts and advice?