Breaking wheel studs

rhagfo wrote:

Dtank wrote:

TucsonJim wrote:
One other possibility that I just thought of. If a shop used a pneumatic gun even once on the lug nuts, they could have fatigued the studs with an over torque situation and they all should be replaced.

Agree with Jim's thoughts - especially the above.

*If* you (or a previous owner) had tires replaced by a tire shop, there's a good possibility an employee used an impact wrench that is/was "supposedly" set to the correct TQ spec - *without* hand TQ.
(Even the factory could be "guilty").

The method is bogus - and the desired spec used may also be suspect.

*If* you know (for sure) this didn't happen - look for other cause/s.

"Fatigued" actually means "stretched".
No way the studs "recover".

Thoughts:
You could replace all the studs - a PITA! -or-
You could repair as breakage occurs - check studs frequently.
Bad karma if more than one stud on a wheel breaks at the same time.

Check for the correct TQ spec for your wheels - via the wheel mfgr.

*ALWAYS* always - watch any/every tire shop employee mounting wheels on any vehicle you own!
Impact wrench is only used to snug the lug nuts. He should then TQ the lugs by hand. Your job to make sure he knows the desired TQ -AND- *watch* carefully!..:W

If his TQ wrench clicks immediately, he's doing more than "snugging" the nuts with the impact!..:(
Call a halt to the installation!

BTW -
High volume tire shops (like Costco) are famous for the above..:(
and -
Tire shop employees may have been working at Taco Bell the previous week..:W

.

Exactly!!!
Impact wrenches have adjustments for the amount of pressure they put out. When the lugs are going back on mine is set at the lowest setting, and as soon as the lug is snug, I stop driving.

I asked Discount about this years ago, and was told that their impacts are just for speed and not tightening. Final tightening is always done by hand, using a torque wrench. IIRC, he (the manager) told me that the impact are set for something like 50 lb ft, and =are= calibrated. You can tell by the sound of the air wrenches that they're nowhere near full capacity; sound is softer, the pitch lower and the impact frequency is slower. They usually get a full turn, or close to it, even on my Civic, let alone on my truck or FW.

Lyle