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Unread 12-29-2017, 12:36 PM
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Default Installing and Removing Screw-in Wheel Studs

Had a customer ask how to remove and replace wheel studs that he had installed with Loctite, per our instructions. So I wrote this quick guide for him in an email and copied it below.

INSTALLATION TIPS



Screw-in wheel studs for a BMW are made to replace wheel bolts - the bane of the automotive world. We sell other types for other cars, but this is our biggest seller.



Instillation is pretty easy - a dab of red Loctite on the end, screw it into the OEM hub to "hand tight" (about 20 ft-lbs), then let the Loctite setup. Done.



There is a raised shoulder separating the inner threaded portion that goes into the wheel hub from the outer threaded portion that the lug nut rides on, shown above. Our goal is to screw-in the stud until this shoulder BOTTOMS ONTO THE HUB.



Use a hex wrench in the broached hex end of the stud to install it, as shown above. There is no hard torque setting given to seat the stud - you can watch it turn in, then it will "lock up" as the shoulder hits the threaded hole. Stop there, you are done. Its all done by hand, so probably no more than 15 ft-lbs. DON'T OVERTORQUE THIS!



If the studs don't want to go in check to make sure you have the right thread pitch studs - line the new studs up next to the old wheel bolts. If the threads sync up and the stud/bolt are the same diameter, you've got the right parts.



Sometimes they still don't want to thread in - usually on a super rusty car. If and the threaded holes in the hub are crusty, you should either A) replace the wheel hubs of B) at least chase the threads with the a chasing tap of the same diameter and thread. Call us and we can explain how to buy one. Rarely needed, but just there in case...



We sell an installation kit with the correct hex wrench, Loctite, and some anti-seize. Just a dab of anti-seize on the outer thread sections (where the lug nut goes) helps give you a more accurate torque for the lug nuts (85 ft-lbs) and also some anti-corrosive properties. If the threads are dry they will have some "stiction" that leads to false torque readings.



The mechanical seating of the shoulder touching the hub and the chemical bond of the red Loctite is what holds it in place over time, when you have the lug nuts going on and off during wheel changes. You can even use an electric or pneumatic impact gun, just DON'T OVER TORQUE THE LUG NUTS with those tools. Set them with 85 ft-lbs using a torque wrench, and no more than 95 ft-lbs.

REMOVAL AND REPLACEMENT

So after a few years of track/street use you will want to replace the lug nuts and wheel studs. These are wear items after all, and if you do a lot of wheel changes (autocross, track use, etc) you are putting a lot more wear on the threads than most folks.



Removal of the screw-in wheel studs is a little trickier... The hex inert in the end of the stud is not strong enough to extract the stud once it is chemically bonded in place.



The best way is to use to lug nuts and screw them together on the stud, as shown above. This is called the double-nut technique, and is used to install and remove studs in many applications.



Once the two are touching snug them together with two wrenches, as shown. Once the two nuts are "locked together" you can turn the inner lug nut and it should remove the stud...



Sometimes torque isn't enough - to break the chemical bond of the Loctite, heat is sometimes needed. Apply heat directly to the old studs, and it won't take much. The heat should break the bond, then use the double-nut technique to get them out. Replace the studs and you are good to go.

Cheers,
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