front differential output shaft bearing
 

I have a vibration while driving 2000 Blazer over 45 MPH.
The front output shaft bearings must be replaced. I know how to remove the shafts, but have been unable to find the bearing removal/installation procedures. There are thrust bearings that will need to be torqued. What tool is needed to do this and what are the the torquing procedures/specks?

How do you know these bearings are bad?? Are the seals leaking? I've noticed that all of these blazers have a little play at the output diff bearings. The passenger side bearing is easy to replace but the drivers side is more difficult. If you're sure the vibration is coming from the front driveline I'd check your CV axles first.

Thanks for the reply.
Both sides have new rebuilt halfshafts. I jacked the truck up and listened with a stethoscope (truck in gear and 4wd at about 40 mph) and the noise was loudest at the passenger side of the differential where the halfshaft plugs into the spline.

Is the half shaft fully seated with the clip locking it in. I have had one pop out on me when i bought a blazer that had smaller front tires on it. when the auto 4 wheel drive kicked in on me it bucked a bit from the different speeds at the two differentials. One half shaft came out a little. enough to not be secured by the internal clip. It made a noise the could resemble a bearing until I popped it back in.

That's not the problem. At speeds to 45 mph there is no problem. From 45 mph to 55 mph there is a vibration from the front differential. This vibration is also present without 4WD engaged when driving at that speed.

If I'm understanding correctly the vibration is still there with the diff disengaged and front tires are not rotating when you had it lifted and the rear tires spinning at 45? If the pass half shaft wasn't spinning I don't understand. If this is occurring while driving the tire is driving the half shaft and the bearing noise is present. If you didn't I'd check with it lifted again with front tires not moving. If the vibration is gone its possibly the u joints. If only there with wheels moving I'd remove them and possibly rotors to. Could be vibration resonating upwards and appearing where there is minute amount of play. That extension shaft comes out as well and exposes the actuating fork and workings. The aneboric sealer, or something like that anyway, is needed to put back on. I thought those bearings just pulled out with a slide hammer and the pinion bearing was a pre-load bearing.

The carrier bearings are shimed with the diff cover off to achieve the correct preload.

I could be mistaken. It been a long time ago on a 2000 blazer since I've been there.

Solution:
I was wrong in my analysis of the vibration. The Blazer has a 4 switch Auto 4WD control that spins the front driveshaft in 2WD and 4WD. I hadn't checked it because I didn't think there was any reason for it to be spinning in 2WD. I had a bad front driveshaft constant velocity joint.