Several months ago I did a clutch rebuild on my 89 Ranger. My first clutch job ever. Replaced pilot bearing and the big carrier bearing. Seemed to go OK.

However, I'm experiencing a rattling sort of noise when I accelerate or decelerate, most noticeably at slower speeds. Also a little thump when I let the clutch back out after shifting gears. It doesn’t sound like it’s coming from the transmission. It sounds like it’s coming from farther back. Someone told me that's a bad u-joint. I hope so, because that's something I think I can fix.

What I'm afraid of is this: when I removed the driveshaft when I was doing the clutch job, I used a dremel tool to grind a small scratch across the differential flange and end of the shaft, to mark the orientation of the shaft. (Manual suggested painting a line. I thought I was gonna be The Big Man using my dremel!)

I'm concerned I did a really stupid thing in doing that. Could such a small scratch be enough to unbalance the shaft? Would an unbalanced shaft make that noise only when accelerating at slow speeds? Everything sounds fine once I'm cruising along at constant speed.

 

An unbalanced shaft would cause a vibration. I would check for ujoint play and replace as needed. Its like a 15 dollar part.