i have a 95 z-71 with 224,000 on it. it just started making a high pitch clicking noise coming from the front of the rear end when you shift from fwd to rev. i checked the fluid and it was low so i added some up to the hole where you are supposed to. the sound isn't a clunk like that of a u-joint. anybody with any ideas would certainly be appreciated. thanks

are you sure it's coming from the diff? if you are take the diff cover off and check the spider gears in the carier. also make sure your fuel lines aren't contacting the body up by the transmission.

It could be too much backlash in the ring and pinion.

it doesn't do it all the time. most of the time when you go from fwd to rev and when you start to accelerate. is there a bearing around the yolk and if so could it be going bad? thanks for the other replies.

i have a problem too... my rearend howls at certain speeds. could this just be that i need to change the fluid and put some posi additive in it? it is a posi 12 bolt.

also, especially when on the highway at steady speeds, i have noticed when i let off the gas, i can feel a clunk kinda like a bad shift will feel like and it does it again when i put the gas pedal down again. what is this most likely? does a u-joint clunk like that when it goes bad or maybe the rear end or even worse my tranny? the tranny shifts completely awesome and only clunks a little bit (the nature of the beast) when it shifts up and stuff sometimes, but mostly its so smooth that the only way you can tell if upshifted is the obvious drop in engine rpms. so is it probably the rearend? i know its not the torque converter unlocking because my torque converter does not have lock up on it

i figured out where the sound was coming from. it was the front u-joint. i reckon the sound was traveling down the driveshaft. one of the caps was broke and didn't have any needles in it. changed both u-joints last night. glad it wasn't in the rearend. thanks to all who replied back to my questions.