hello I just bought a xj and they did a brake convert on my rear from drums to disks but it sound like rubbing can any one help me plz

 

metal on metal rubbing? worn pads? Its coming from the rear? a plastic rubbing? a little more info would be nice to narrow down possibility's. the backing plates could also be bent rubbing on the rotors.

 

I'd start by jacking up the rear, putting it in neutral and spinning the tires by hand, you might be able to narrow it down that way.
Something like thats kinda hard for anyone here to help you with, kinda hard to diagnose a sound over the Interwebz.
Might try searching, Rear disc conversion making noise or something like that here and on Google. Good luck.

 

I've seen pebbles get caught between the backing plate and the rotor as well. Pretty rare but I've seen it more than once.

 

Pads and rotors are new and yes in the back. But what causes the pads to rub on rotor

 

Well, it's normal for the pads to rub the rotor on disc brakes. Unlike shoe brakes, which have return springs to pull the shoes off the drums, disc brakes have no return springs. If they rub too much when you're not on the brakes they might just need some high temp brake grease in the slots where the pads slide back and forth. Clean 'em up, then grease 'em up. Also, you'll notice two bolts with rubber boots on them. Those bolts should slide freely as well. You can pull them out (the bolts) and remove the boot (carefully) to clean and grease the inside.
That done, loosen your brake fluid reservoir cap and make sure it's not too full. Use a large C-clamp to squeeze the caliper piston back into the caliper. It should move relatively easily. Make sure fluid isn't overflowing your reservoir. If the calipers seem ok, no leaks or torn seals, then they should be ready to go. If not, maybe there IS a rock stuck in there hope this helps.
p.s. Don't depress the brake pedal with calipers off.. it's messy!

 

seen this a few time too. Also good starting point of jacking up the rear end and turning it by hand looking for the noise. should narrow it down pretty good.

Does it change at all when you apply the brakes? is it constant or a rotational sound? does it get louder with speed?

 

Take the rotors off and adjust the drum pads they did not convert witch is like the ebrake on disc purpose only on disc. U bet thats what is rubbing

 

Rj said it right thats what was goin on they did not pull the drum pads off that and it was rubbing on the inside of the disk brakes