The short version
- Studs are pressed into the hub flange and knurled to stop them turning.
- On a bolt on hub unit, the studs come with the new part, so this becomes free.
- Pulling one in with a lug nut and washers works, but it can crack the hub flange.
- The new stud must seat fully flat against the flange or the wheel sits crooked.
You have the hub out, the new bearing ready, and one stud needs wheel stud replacement for stripped threads or a rounded shoulder. It usually gets noticed at exactly this point.
The good news is that this is the easiest moment in the vehicle’s life to fix it. The hub is already out and the flange is accessible.
Wheel stud replacement starts with how it is held in
Not by thread, which surprises people.
Studs also get damaged freeing a seized wheel. The stud passes through a hole in the flange. A splined or knurled section sits just under the head.
Pressing it in cuts that knurl into the hole, which stops the stud rotating when a lug nut is tightened.
That knurl is why a stud cannot simply be unscrewed, and why the replacement has to be pressed rather than threaded in.
The part that decides the whole job
A bolt on hub assembly is supplied complete with studs already pressed in. Replacing the bearing replaces the studs at the same time.
If that is what you are fitting, there is nothing to do here beyond checking they are all straight and clean.
Which design you have is on the design comparison.
Where the hub flange is reused, or where the studs sit in a drum or a rotor hat, this becomes a separate job. The bearing procedures are on the pressed in page and the repacking guide.
Getting the old wheel stud out
Three routes, and access decides which.
Press it out with the hub on the bench, supported around the hole. This is correct and damages nothing.
Drive it out with a hammer and a drift, striking squarely on the threaded end. Effective, and hard on the bearing if the hub is still assembled.
Rotate the hub so the stud clears the brake backing plate. That is often the only reason a stud will not come out on the car.
Every blow travels through the rolling elements of the bearing you are trying to protect.
If the hub is apart anyway, do it on the bench. If it is not, that is an argument for pressing rather than hammering.
Pulling the new one in
| Method | Notes |
|---|---|
| Shop press | Correct, controlled, needs the hub off |
| Lug nut and stacked washers | Common, works, stresses the flange |
| Dedicated stud installer | A puller frame with a bearing, the best on car option |
| Hammering it in | Never. It will not seat square and it damages the threads |
Grease the washers and use a thrust washer or a small bearing so the nut turns rather than dragging on the stack.
Tighten steadily and stop the moment the stud head contacts the flange. Continuing past that point is what cracks flanges.
Sacrifice the lug nut you use for this, since its threads take a hard life during the pull. Torque figures for the finished job are on the torque specs page.
Getting it seated
The check that matters, and it takes seconds.
The head must sit completely flat against the back of the flange. There should be no gap anywhere around it.
A stud sitting slightly proud holds the wheel off the flange at that point. It shows up as a vibration nobody can find.
How small a gap it takes to cause that is on the vibration page.
Choosing the replacement wheel stud
- Match the thread, since a hub can carry metric or imperial studs depending on the market.
- Match the knurl diameter, which is what actually holds it, not the thread size.
- Match the length, because a short stud loses thread engagement in the lug nut.
- Buy a spare, since the second one usually reveals itself while you are in there.
Extra length only helps if the nut can reach it, and it can foul the brake hardware behind the flange.
If threads are stripped, the stud is the part to replace rather than the thing to work around.
The tool that saves the hammer blows
Wheel stud installer tool
Draws the new stud through the flange with thread pressure instead of hammer shock, which the fresh bearing behind it will appreciate.
On some hubs a stack of washers and a lug nut does the same job more slowly.
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Common questions
How does wheel stud replacement work?
Press or drive the old one out, then pull the new one in with a press, a stud installer, or a lug nut and greased washer stack.
Do studs come with a new hub assembly?
On a bolt on hub unit, yes. Replacing the bearing replaces the studs with it at no extra cost.
Can I hammer the new one in?
No. It will not seat square, the threads get damaged, and the blows travel through the bearing.
What stops a stud from spinning?
A knurled section under the head that cuts into the flange hole as the stud is pressed in.
How do I know it is seated?
The head sits completely flat against the back of the flange with no gap. A stud slightly proud causes a vibration nobody can find.
What do I match when ordering a wheel stud replacement?
Thread, knurl diameter and length. The knurl is what actually holds it, so matching the thread alone is not enough.
Should I replace all of them?
Not necessarily, but check them all while the hub is out. The second bad one usually appears at the worst moment.