Front Spindle nut tightening. Need help please

[TheBandit]

The way I did it was to use a smaller 3/8 drive torque wrench which I set to 144in-lb (12ft-lb) to tighten the spindle nut, then I rotated the rotor a bit, then re-torqued and repeated a few times to make sure the bearings were fully seated. Then I backed the nut 1/8 turn looking for the nearest cotter pin hole. The goal is to have zero preload on these bearings with minimal axial play. I have seen a spec of 0.003in maximum axial play.



Torquing the nut to 12ft-lb helps establish where the bearing has just slight preload. Then backing off by 1/8turn provides the axial endplay required to ensure it's not overly preloaded when things heat up under use & braking.

A typical GM spindle nut has a 3/4-20 thread, which is a pitch of 0.05 (one revolution will move the nut 0.05in). To get 0.003in axial play, you can rotate the nut 0.003/0.05=0.06 times which is about 1/16 rotation. With 3 options on the nut and 2 options on the spindle, you should find a nearby position that allows the cotter pin to go through.

Also don't forget to install the tabbed washer that must sit under the spindle nut. The tab keeps the washer from rotating which is important to make sure the nut doesn't try to back off.

[72Z/28]

The way I did it was to use a smaller 3/8 drive torque wrench which I set to 144in-lb (12ft-lb) to tighten the spindle nut, then I rotated the rotor a bit, then re-torqued and repeated a few times to make sure the bearings were fully seated. Then I backed the nut 1/8 turn looking for the nearest cotter pin hole. The goal is to have zero preload on these bearings with minimal axial play. I have seen a spec of 0.003in maximum axial play.

Torquing the nut to 12ft-lb helps establish where the bearing has just slight preload. Then backing off by 1/8turn provides the axial endplay required to ensure it's not overly preloaded when things heat up under use & braking.

A typical GM spindle nut has a 3/4-20 thread, which is a pitch of 0.05 (one revolution will move the nut 0.05in). To get 0.003in axial play, you can rotate the nut 0.003/0.05=0.06 times which is about 1/16 rotation. With 3 options on the nut and 2 options on the spindle, you should find a nearby position that allows the cotter pin to go through.

Also don't forget to install the tabbed washer that must sit under the spindle nut. The tab keeps the washer from rotating which is important to make sure the nut doesn't try to back off.

Thanks for the input. I am using the a small torque wrench as well in in-lbs. i have been the same thing with spinning the rotor and maintaining the torque at 144 inch. Lb.

I did back off the nut 1/8 of a turn but still there was a preload on the bearing.

[CarlC]

I've tried every method and only one offers a consistent preload setting, the Kore3 solid bearing spacer with shims. When properly set up the 0.0015" end play wheel movement is minimized and and bearing life maximized.

1) Install the hub + bearings on to the spindle without grease or the inner seal.

2) Using the provided shims, adjust until an end play of 0.0015" is met.

3) Disassemble and pack the bearings full, internal housing and cap 1/3 - 1/2 full of grease, install the seals, and reassemble using the same shim and spacer pack.