Lil Jimmy ('91 T-15, 4.3L TBI, 4x4) just isn't feeling well.
Here's exactly what it does. I back out of the garage straight into the driveway and it may pop/clunk once over the fifteen foot journey after it starts rolling. I continue backing out (slowly) while cranking to the right and it'll pop twice more during the turn. If I go further backwards it's fine. I put it in OD and straighten out the wheel and sure enough it pops maybe ten feet down the road, usually followed by two more within the next thirty feet or so. After that it's fine for the 25km trip to work, not a single clunk (aside from a damaged exhaust).
Here's what has me puzzled. When I eventually stop and leave it for a while, if I take off in the same direction I parked it in it appears to be fine. I can put it int neutral at a light and let off the brakes just to relieve all tension in the driveline, and again, it's nice and quiet taking off again. It only seems to happen while switching from forward to reverse, far worse while turning, regardless of my spiritfullness with the accelerator. It sounds and feels exactly like a clunking CV joint (they're fine), and it is felt through the floor under my left foot. Nothing is felt through the steering wheel, and the only thing banging around over bumps is the exhaust (definitely a different sound).
The torsion bar mounts are fine, as are both half shafts, the upper ball joints, the lower ball joint on that side (I'll try to get around to installing the other one tomorrow) the idler arm, and the hub assemblies. The pitman arm and the tie-rod ends don't show any unusual play, and the control arms won't rock back and forth at all by hand so I assume the bushings are decent.
All I can guess is a worn but still tight to the touch U-joint, but I'm grasping at straws at this point. Any suggestions? I'll check the tranny mount when I check the U-joints just for the hell of it.
Oh and as a side note, is there a special trick to replacing the lower ball joint? That damned thing took me three and a half hours to install the other night, and that was just one of them! I had hoped that it was as easy as the uppers but I had to pull the transaxle (again) and wrestle it around the LCA. I'm considering popping the upper joint as well when I tackle the other side. Surely there must be a better way...