Snapped wheel stud again

[ranjag]

Has anyone ran into sheared wheel studs on the front hubs.

I just noticed 2 of the front wheel lug nuts were sheared off the hub on the drivers side wheel.

I have a set of Rota RB 15" rims on the car and was wondering if the hub may not be centred on the wheel causing stress on the wheel studs.

The same thing happened on the passenger side a few months ago when I noticed the wheel was loose and one of the studs was also sheared off .Now that its happened again Im wondering if I have the wrong lug nuts on the rims or a wheel to hub centering issue.

I know for a fact I didnt over tighten the lug nuts when I first intalled the Rota RB's and they were tightened to 80ft lbs.

 

Any suggestions?

 

Sent from my SM-G930W8 using Tapatalk

 

 

[Dudeland]

IMHO those don't look like stock studs.   I just finished replacing the studs on my 75 with IE ARP extra long ones, and the ones I took out had threads much further up the shaft. 

 

It is late.... maybe my eyes are playing games. 

[AceAndrew]

 

The rule of thumb is to have AT LEAST a thread engagement depth equal to the diameter of the stud (so with a 1.5mm thread pitch on a 12mm stud means you need at least 8 full turns).  From your picture, I'm guessing that there was not enough thread engagement running those wheels on stock (yes they are stock) studs, so the fully torqued the lugnut over-stressed the end of the stud and allowed it to shear where it did.  

Edited March 26, 2018 by AceAndrew

['76mintgrün'02]

4 hours ago, ranjag said:

they were tightened to 80ft lbs.

 

Torque specs state 59-64 lb-ft, (or 81-89 Nm)

[TobyB]

Might just be the pic, but those studs aren't square to the hub-

 

sure your wheels are 100mm bolt circle?

 

Typically an overtorqued wheel stud pulls through the hub flange,

shearing off a cute little ring of studhead....

 

t

[Preyupy]

4 hours ago, TobyB said:

Might just be the pic, but those studs aren't square to the hub-

 

sure your wheels are 100mm bolt circle?

 

Typically an overtorqued wheel stud pulls through the hub flange,

shearing off a cute little ring of studhead....

 

t

I was wondering the same thing Toby,  it could just be the wide angle lens but they don't look square to me either.  And 80ft/lbs is 30% above the factory torque setting (and I'm sure you are not the first one in the last 45 years to over torque them) 

 

Check your wheels, then replace ALL of the wheel studs and use the correct torque specification.

[mz_90292]

I realize this is an old thread, but purchased Rota RBs about three months ago. I had the same thing happen where the nuts were torqued down to spec and the left front hub had two lugs snap. I had recently replaced the two front hubs when I was going through my suspension/ brakes/ etc with brand new BMW parts so everything was correct in angle relative to hub/ thread showing etc.  
 

Since the incident, I have been checking the torque on the nuts before every drive. I’ve found that after a spirited drive or 50 miles or so every wheel is fine except for the front left. Always needs an 1/8th- to a quarter turn to torque down per nut. Is this an issue with these wheels? Are some manufactured just off a bit that could cause a wobble and the nut to slip? The wheels were mounted and balanced by a trusted shop so I can’t imagine an issue there. 
 

Slightly relieved I’m not the only one, but still perplexing. If anyone has any suggestions it’s appreciated. I’ve hear of torquing to 70-75 lbs due to the softer metal (aluminum vs. the stock steel) but worry of added pressure resulting in the same end. 

Edited February 29, 2020 by mz_90292

['76mintgrün'02]

Forgive me for asking, but you did replace the stock steel nuts with nuts that fit alloy wheels, right?

 

(The angle on the taper is different).

 

Sorry, for stating the obvious... 

 

Tom

[mz_90292]

Ha! I thought the same thing. I did and then in disbelief that it happened, double checked again after the incident thinking I missed something. 
 

Thanks for the reply. 

[Conserv]

And, just to confirm, are you using spacer rings with the rims? And are your studs stock length?

 

I wonder if a Rota RB might be a bit thicker from hub-face to lug nut seat than other rims, forcing the lug nut too far out on the stud.

 

Regards,

 

Steve

 

Edited February 29, 2020 by Conserv

[RH002AJ]

Hello
■ Why don't you look for “hub centric rings”? 【← I agree with Conserv】

■ An oil film is visible on the front hub (wheel mounting surface) of ranjag, but I think that the oil should be sufficiently removed.
(Let the studs and nuts be degreased as well)

We hope the success··

[RH002AJ]

I just noticed that it was the topic of 2018.
Please ignore my comments.

[mz_90292]

Conserv,

 

thanks for the reply, no spacers on my car and stock stud lengths, almost brand new hub and studs before I put the wheels on, a couple thousand miles at most. 
 

The strange thing is that all three of the other wheels have zero issue, making me think the hubs/ studs are not the issue. It’s just the front left wheel that gets loose and needs tightening. 

[Conserv]

58 minutes ago, mz_90292 said:

Conserv,

 

thanks for the reply, no spacers on my car and stock stud lengths, almost brand new hub and studs before I put the wheels on, a couple thousand miles at most. 
 

The strange thing is that all three of the other wheels have zero issue, making me think the hubs/ studs are not the issue. It’s just the front left wheel that gets loose and needs tightening. 

It just seems too coincidental that you and @ranjag both run Rota RB’s and both have front hub issues. Maybe lots of others have similar issues with other makes of rims — and we simply don’t hear about them!

 

Regards,

 

Steve

 

Edited February 29, 2020 by Conserv

[TobyB]

So, on the raceycars, this happens with heat- we retorque them hot, and they're usually

quite loose the first time.

 

But it also happens when the wheel doesn't sit exactly right on the hub face.  Is it 

possible that some part of the center bore is touching the hub, so the face of the 

hub's not getting clamped to the mounting face of the wheel?

 

Guess what I'm asking, is,  is the wheel moving on the hub?  That lets things wear,

the nuts pull into the aluminum of the wheel, and it gets loose pretty quickly.

 

About 2 laps, if you didn't snug down the rotor retention screw on the E21 and later rotors, it turns out.

 

t