i have a 98 ram making grinding n whining niose from the rear end n i all ready checked the fluid n i pulled the magnetent out n it had some metal on it. now my ? is couldit be bearings or opionan or some else lil cus it stil drivesjus find it jus has a terrible niose

 

are you noticing the noise more at lower speeds. could be a pinion bearing. I had the same thing, just had the rear end rebuilt. pinion bearings,carrier bearings and axle bearings.

 

mine used to whine when i let off the gas (standard tranny) then one day it got louder then the next day the rear end locked up at 65 lol

 

im having the same problem as the OP. its probly the pinion bearing. time to get that replaced guy or it could end bad. hey look at it this way. good excuse to install new gears!

 

roaring, whining, or howling is probably just some worn out bearings or gears that could probably run on for a while.

grinding noise is not good. were you able to feel, hear, or see the grinding when you had the cover off?
and do you have an LSD or OPEN diff. LSD can contribute some extra noises.

i'm not sure i'd drive it with a grinding noise.