Well, I guess that I'm lucky or something because I've had the pleasure of replacing 3 wheel studs recently. I change wheels for auto-x and I'm guessing that is the reason it happened. Anyway, I found out that it was much easier than originally expected and I wanted to let everyone know how. There was no need to have any special tools or remove anything from the suspension or brake system. I completed the job with the brake rotor in place and the only thing I removed was the wheel.

Tools needed:

Torque Wrench
Mallet
Socket for wheels nuts
Wheel Stud for front (part number : F151-33-062) (about $4.97 from Mazda)
Several large Washers or Nuts (you'll see later)
Impact Wrench
Floor jack and jack stands


First, raise the car and remove the wheel.
The damaged wheel stud can easily be removed with a few hits from a hammer or mallet.

Next, align the the hole to the right by the brake caliper. This is spot that allows access from the rear to insert the new wheel stud.

 

When the whole is to the right, you'll be able to look back from inside the wheel well and see the whole. Actually, you'll have to feel for it, but this is how the stud is inserted back through the hub and rotor.

You can push the stud through from the back and pull the it all the way out of the rotor.

 

Then, I use the large washers and nut as a spacer to pull the bolt all the way through and set it into the hub. This is where you will need the impact wrench. The washers act as a spacer and the standard wheel nut pulls the stud in place.

I had to start with about 4-5 washers at first and then use a couple washers with the large nut to make sure the stud pulled all the way in. I had to feel from the back to make sure the stud was all the way in place. Also, the impact pulls the stud in pretty steady until the stud is in place. You'll be able to tell when the stud is set. Once you feel the extra resistance on the impact wrench and feel the back of the stud is against the hub, it's done.

 

Next, to ensure proper stud fitting, you can measure the stud from the rotor. It should be out 1 inch.

Finally, look at the crappy old wheel studs with disgust before throwing them in the garbage.


That's it, it was pretty easy. If anyone has any questions, please let me know. Take care.

 

Lego,
Thanks for the DIY.

2 questions --
Why do you feel the studs are stripping?
Is the impact wrench imperative, or would a slow draw-up with a ratchet be as effective?

 

No problem. Glad to hear from you. You'll have to join us for our next outing.

The ratchet would work too, it'll just take a little longer. The studs were stripped because when I tried to remove the nut to change wheels, they one wouldn't come loose and had to be broken off, and the other came off hard. When I checked, the threads were stripped. I always torque to 75 lbs/ft. religiously, so this is starting to upset me. I don't know if they are going on ok, and then getting knocked loose or something. I think I'm going to start using antisieze on the studs.

 

I had 6 studs break on me. I think there is an issue with weak studs on our 8's. A large number of people are having the same problem.

 

The stock spec for the Lug nuts is 108ft/lbs....that's very high and probably causes the stud to stress fatigue after repeated re/re of the wheels.

 

I've started to put antisieze on my bolts now. Also am torqing to 90 lb/ft. Mazda should have made the rear bolts easier to replace!

 

Does anyone know the size of the studs? I was told that they are 12mm. Just wondering.......

 

....best stuff made!

I know a few purists object to the use of anti-sieze compound on wheel studs, because they could come undone, but the fact is - they don't.

Most enthusiasts take their wheels off regularly, for swaps, for race days, or just brake checks, but other drivers may have a nasty surprise after a winter of salty driving, when tire time comes. Broken studs, stripped or siezed threads are no fun.

Here at the oil refinery, we use Never-Sieze on EVERYTHING threaded - no compound; no inspection pass......and the reactor head bolts never "come undone"!!

While you have the wheel off, put some on the bolts holding the caliper in - another surprise you don't need! I removed the screws holding the rotor in place and coated them - when I came to put my drilled/slotted rotors on, I found I could use a screwdriver instead of having to DRILL the screws out!

S

 

this DIY is not correct for stud removal

You DO NOT want to hammer out wheel studs, it will damage the bearings if only even ever so slightly, the bearings are rollers so when you hammer on the stud you are creating indentations at the roller/seat mating surfaces

best to remove the rotor, unbolt the bearing hub assy from the spindle, and either support hub flange on something while you hammer them out or use a c-clamp/vise to press them out. You may be able to press them out with a c-clamp on the car if there's enough room behind the flange to fit an oversize deep socket to press it out against

fwiw, the real issue is the OE lug nuts/locks, they gall easily and F the stud, replace them with quality nuts/locks and you won't likely have an issue

I haven't ever had to replace a stud on this car despite numerous wheel dismounts and 108 lb-ft retorquings

the studs are 12 x 1.5, somebody posted the lengths somewhere on the forum, do a search, they are different front and rear, BTW replacing one on the rear is not so easy ...

 

No, you're right, there is no room to get in there for the back. You have to disassemble the whole wheel assembly and press out the bearing to do it right.

I didn't know hammering them out for removal was a bad idea. That is what Mazda did, so I just reapplied. I did remove the rotor yesterday to get it turned. It wasn't that hard.

 

I had to drill out both set screws in each rotor to remove it...what a bitch.

 

Hmmm I better get some high quality nuts to prevent this nasty issue. Thanks for the tips.

 

i have a broken stud too and tried to hammered it out, but it didnt come out. have any better idea?

 

WD40 it first, then you hammer it out with a heavy *** hammer and a small screw driver.

 

NICE WRITE UP， this really works well. since my old stud was burnt, a flat head screwdriver can really stick in. i still used the same hammer and this time i let someone hold the screwdriver for me, i hammered it pretty hard and it suddenly came off. Thanks to this DIY ,the writer, and nycqps.

 

front studs are M12 x 1.5 thread with a 0.506" knurl diameter and 0.335" knurl length

just replaced mine with longer ARP racing studs (listed as part#100-7719 for the Miata)

removing the hub is super easy, DO NOT hammer these off on the car or you risk damaging the bearing with the hammer blows

1. jack up wheel and support chassis with a jack stand
2. Remove front wheel
3. Unbolt flex brake line connection from upper control arm; 12mm socket, 1 bolt
4. Unbolt brake caliper and support properly to the side with wire or coat hanger; 14mm socket, 2 bolts
5. Unbolt caliper mount; 17mm socket, 2 bolts
6. Remove ABS sensor connector from rear of hub by inserting small flat blade screwdriver in slot at the lower back, rotate/swivel it upward to release connector hook while wiggling off the connector at the same time
7. Unbolt and remove wheel hub assembly from the spindle. The brake rotor backing plate will come off with it; 14mm, 4 bolts

the lug bolts can then be removed by supporting the hub surface properly, a press is preferred but they can also be hammered out by setting the hub on top of a long socket, piece of pipe, etc. centered under the stud to support the hub surface. Took me less than 30 minutes per side to do all of the above and then I took the hub to a shop and had them use a press to remove and replace all of the studs.

To install just reverse the removal procedure.

NOTE that the rear studs have a different part# than the front studs!



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