Rearend rattle.

Everytime I hit a bump in my XJ my rearend makes a sort of clunky rattle noise, and when I get out and kick the wheel I can hear a slight clunk noise. A friend kicked a wheel and told me it sounds like my brakes which very well could be it because when I hit the brakes I hear a loud click coming from the passenger rear brake. Is this the brakes, axle or something else? And is it safe to drive like this until I can get it fixed?  

it could be brakes. i do believe those are drums in the rear. the best way to find out is to take it apart and look for broken parts. maybe a spring let go. drums are low maintainance and fairly easy to work on, as long as your careful with the springs. also, lift your rear tires of the ground, one at a time, and give them a good shake back and forth. there should be no play in them. if there is, that could be part of your issue too! good luck  
99 cherokee sport with a costume front bumper. 7 inch optronic lights 30 x 9.5 goodyear wrangler GS/A tires and TJ flares modified to fit my Jeep

What could it be if they do move back and forth? I just drove it about 50 miles yesterday without any real trouble but it still makes that noise when I hit bumps.  

wheel bearing. a machanic friend of mine was checking out my cherokee cuz i had a weird noise. and im pretty sure thats wat he said he was checking in the rear end. if youve ben in the mud recently and the noise started just after you did, than it could be some mud in your brakes. my brakes were making a grinding noise and just spraying some brake cleaner into them front and rear made a big differance.  
99 cherokee sport with a costume front bumper. 7 inch optronic lights 30 x 9.5 goodyear wrangler GS/A tires and TJ flares modified to fit my Jeep

Well it's deffinently not mud, it's a metal on metal noise, kinda clunks as if the axle is just bouncing around in the housing.  

its coming from the differential? how bout those wheels? did they have any play in them?  
99 cherokee sport with a costume front bumper. 7 inch optronic lights 30 x 9.5 goodyear wrangler GS/A tires and TJ flares modified to fit my Jeep

It sounds like the brakes to me, it deffinently ain't the wheels and it sounds like it's coming from the ends of the axle rather than the center.  

ok. deffinatly would take the wheels off and check those brakes for loose or broken springs. and check your shoes for wear. if its metal to metal sounding than it could be that. good luck.  
99 cherokee sport with a costume front bumper. 7 inch optronic lights 30 x 9.5 goodyear wrangler GS/A tires and TJ flares modified to fit my Jeep

I will, Jeeps still sitting at my dad's so I won't be able to check till sunday but I'll post my findings, thanks.  

good luck. i hope it works out for you. your welcome.  
99 cherokee sport with a costume front bumper. 7 inch optronic lights 30 x 9.5 goodyear wrangler GS/A tires and TJ flares modified to fit my Jeep