Installing Wheel Studs

[Dime Dave]

After some recent email correspondence I thought it might be prudent to offer a guideline for installing wheel studs. 

 

First, let's discuss the design of a wheel stud and fitment during their original installation.

 

When first assembled, the hole in the hub / wheel flange has a smooth bore. For proper fit, the hole ID needs to be .006" smaller than the OD of the knurl on the stud. The stud is then pressed into the hub from the back side and the knurl actually deforms the ID of the hole in the hub. This deformation is what holds the stud in place and keeps it from rotating. 

 

Now what about replacing the studs. Wearing my vendor hat, I must say that wheels studs should always be pressed into place. 

 

The reality is you can do this fairly easily on the front hubs. Pressing in studs on the rear isn't really viable unless the rear axle shaft is removed. Generally rear wheel studs are "pulled" into place by putting the stud thru the wheel flange hole and drawing it into place by tightening a nut onto the stud. 

 

The problem with pulling a stud into the hole comes from over tightening the nut. Even though the hub has a pathway for the knurls to follow, it still can take a significant amount of strain to bottom a stud. The OE torque for a Datsun M12x1.25 stud is 58-65 ftlb. Our long studs are 10.9 grade and should be fine to 85 ftlb. If you exceed this torque rating it is possible to damage the stud.

 

If you choose to pull in your new studs, watch how much torque you place on the stud.You should keep it below the rates above to assure the stud is not being damaged.

 

DO NOT use an impact wrench! A 1/2" Dewalt impact wrench with a full charge will generate 185 ftlb of torque and will stretch a stud if you hammer on it long enough. Trust me, been there done that.

 

If significantly over torqued, the stud will be structural compromised and may break. It could be when you bolt on your wheels or when you are happily cruising down the road. 

 

Please use caution when installing wheel studs. Improperly done, the results could be devastating.

Edited August 28, 2018 by Dime Dave