How Tight Should The Wheel Bearing Nut Be After Installing Rotors?
by Monkey Wrench on Wednesday, November 11th, 2009 | 7 Comments
on GMC Safari 1997, cause I have a problem, I thight it up, drive for a few feet, and it comes loose, and my breaks lock up, and after few minutes it releases again 
Sounds like the bearing races are not seated in the new rotor. Torque them down to 50 or 60 ft-lbs then loosen slowly until your rotors spin freely.
you always want to put a load on the bearings, so the rollers are tight against the bearing race or cone, im assuming you installed a tapered cone bearing. you want the bearing to be tight because if the bearing is loose you will cause it to spin, it will spin with the race against the weel hub, and that’s not where you want the spinning to occur. the way you tell if the bearing has a proper load on it is tighten it up to that you can spin it about one full turn with the flick of your hand. so spin it with your hand and it should do a 3/4 turn to a full turn if you have the proper load on it. this will prevent the bearing from becoming a spun bearing. eventually the rollers will go from cylynders to blocks because they are not rotating like they are designed to.
As tight as the SERVICE MANUAL says it should be.
$19.99 well spent.
Need to check the maintenance manual. Most GM products have a torque setting. Sounds like you are not getting complete seating if it get that loose. If everything is assembled right and you run the nut down tight while spinning the wheel, then back off to first jey hole, should never get loose enough to lock the brakes.
either one or more of the parts are not the right ones or are installed wrong. Get a Haynes manual for 10 bucks and check for proper installation. if the parts are installed in the right order then one of them is the wrong part or the spindle is damaged. Are the rotors new? they could be the culprit.
Wheel bearing nuts should be set initially very tight then backed off gradually until the wheel turns smoothly. When I got lazy and had a shop replace my bearings and race ( the round, curved ring they sit in) my wheel soon woobled. I had to jack up the car and use about 1400ft lbs of torgue to set the race and then back off.
sounds like something wrong with the way its put together or you got the wrong bearings…
if you just packed the bearings you need to tighten the nut snug spin the rotor then tighten again till it stops getting loose when you spin the rotor… doing this you are working the excess grease out and allowing the actual bearing to make contact with the bearing races..
But even with doing that. I can’t understand the bearings getting loose enough to lock up the brakes…
or could it be you have the bearings so tight that when they get hot they are locking up the wheel.. and its not actual the brakes locking up?
Good Luck… I agree it would be a good investment to spend 20 on a manual…