clicking noise

Hi, I have a 94 Rodeo 4x4 and I am finding clicking/grinding noise at the rear of the truck. It only happens when I am turning and accelerating hard and to a lesser degree when i accelerate hard going straight. Also have notice that it happens when I use the "power" feature to gain more acceleration. No noise is heard during normal acceleration or at highway speed. Thanks for any info.
Aaron

worn out u-joint? reach under your truck and grab the drive shaft. if it has alot of play, get it checked out. May also be worn out bearing in differential

My best guess would be a worn out diff bearing. This is due to the fact that under load (say when you press the gas) the helical cut of the ring and pinon gears try to force eachother apart. The bearing retains this outward movement of the gears, if this bearing was faulty this would not only make the bearing produce noise, it would either shift the pinion or ring gear out of their ideal contact pattern and make the grinding noise that you referred to.