what are the signs that your wheel bearings are going bad? or have already gone bad?

ive also heard that in 4x4s you have to replace them and cant just regrease them. is this true?

 

on a D30 it's a sealed unit that is greased for life.
They pretty obviose when they going like rubbing our grinding noise coming from that wheel or jack it up and that wheel will have alot of play up and down and side to side

 

so if it goes bad, the whole unit needs replacing? ive been hearing a squeeling from the wheels at a constant speed without applying the brakes, is that the wheel bearing or something else entirely?

 

Assuming this is the front. I'd jack it up and check for any play in the wheel and then pull the wheel off and check the brakes and the axleshaft u-joint.

 

yea deffently sounds bad..like dan said jack it up and see if it moves

 

is that the only thing that would be wrong. anything else that could be the squeeling?
someone told me that its the pads that need to be replaced but i have semi-new discs and pads.
or could it be a warped disc?

im mind blown when it comes to anything related to the axles and brakes.

 

alright i jacked up the front end, tested the wheel. it spun fine with a small squeel every half roatation.
this is the right side tire.
so now is it certain that the bearing is bad? if so do both bearings need to be changed at the same time?

 

when its jacked up you have to try and wiggle the tire and if it moves around the bearing is bad and you do not need to change both at the same time..in my experience with my ford explorer wheel bearings go bad alot off road so i would wait for the other one to go bad before changeing it...and brake do have a sensor thing that makes a squel but it mightnot be that

 

do what he said, it is the best way to find your problem

 

yeah, being in high school still, it will turn into a week long project to take everything apart and check everything.
so what all should all be checked?
axleshaft u joint, entire brake system, wheel bearings.. what else?