If you suspect the U-joints, you should be able to crawl under yer truck and try twisting the drive shaft by hand back and forth. If there is any significant play you can find out with that quick check.

Fer a more in depth check, you could just pull the drive shaft out and check each U-joint fer play. If there is a bad one, it will become very apparent as the one that sticks or wobbles. <img src="/forums/images/graemlins/wink.gif" alt="" />

1998 T-100 Xtra cab SR5 2WD Auto; Roadmaster Active Suspension; Yokohama Geolander HT-S; lowered air dam; full belly pan; 4? diffuser; 11" side skirts; dual transmission coolers; 67% grill blocked; Auto-RX'd; ScanGauge II/Ultra-Gauge