Drive Train Rattling Noise - Second Opinion
1997 Jeep Comanche - 4.7L, AW4, NP231, D44 Rear
Assume everything has 412 miles on it except for the the transmission and transfer case which are both are about 220,000 miles.
Transfer is in 2WD and the front drive shaft is removed since it needs the centering ball rebuilt before being reinstalled. No linkage hooked up either.
There is a rattling noise between drive and deceleration during coasting when the drive shaft is best described as unloaded. It sounds like a dragging chain.
My initial finding was that the drive shaft was built with a low clearance yoke at the transfer case causing it bind at 12º of u-joint angle. It normally rides 10º*to 12º. I remedied that by swapping the high clearance slip yoke from a spare XJ drive shaft to get a maximum of 20º of clearance.
The noise initially seemed to be gone, but modulating to keep the drive shaft unloaded brings the noise back. It just seems that the new drive shaft with the wrong yoke helped to make me aware of the issue.
I am fairly sure it is a loose chain or a bad bearing in the transfer case since the noise is coming from the transfer case area right next to the driver's seat. Though I have other mechanic friends telling me it is probably not that. Thus, second opinions from those with experience with kind of situation?