"Tightening the Wheel Bearings": Its amazing how many errors can be found in GM Service Manuals and Literature. To correct these they put out "Service Bulletins", "Warranty Bulletins", "Service Updates", "Service Notices,"; posted updated "Service Procedures" in the "Service Newsletter", etc.
The correct procedure is to torque the wheel bearings to 25-30 ft. lbs. while rotating the tire. Then back the nut off one-half turn and then tighten it finger tight and insert the cotter pin. It may be necessary to back off the nut to the first position that the cotter pin may be inserted. Remember, there are several slots in the nut, and several holes in the spindle for the cotter pin, so it will not have to be backed off very much.
I almost hate to throw this in, but all new GM vehicles had the grease cups filled to the half way point, and a considerable amount of grease inside the cavity on the drums between the bearings. I found a "Service Update Bulletin" about the time when our coaches were new that confirmed this. The drum was to be filled with grease to the mid line of the outer bearing. This obviously was to keep the bearings well lubricated and allow the grease to flow into the bearings.
Before anyone screams; yes, I have seen many bearings that were greased and installed without all this grease, but since we are draging around 12000+lbs, on automobile bearings it might be a good practice.
