Breaking wheel studs

[Wind_Surfer]

Thought I would ask the collective for help.

I have now had 3 lug nut wheel studs break. Rig is a 34ft, 14,400 GVWR with 16 inch 8 lug aluminum wheels, studs are 9/16"dia. Studs have broken only on the passanger side, two broke on the front and one on the rear wheel. Torque specs are ~120ft lbs. I have a nice torque wrench and check the lug nuts before each trip and during a trip if it's a long haul. What I notice is that a nut won't torque up and of course it has broken. Seldom do the nuts need tightening.

Any ideas on why the studs are breaking?

[oldtrojan66]

I had nearly the same problem last summer. I have Dexter 7200# axles and 16" alum wheels, eight lug. After checking torque at about 12 miles from home and checking for heat only at about 75 miles, we arrived at the campground about 120 miles away.

While backing into the site with mirrors, I noticed the front driver trailer wheel was listing pretty badly. I stopped, got out to look and found the wheel hanging on by three of eight lugs. Three were broken at the wheel, two more had no lug nuts on and one of the remaining three was loose. Of the three other wheels, not one was less than the 100# torque I had set at home.

The only potential cause we could find was the hub was cracked across the braking surface, but it had been for a good while as it was rusted. Now, I have a new hub with studs, another complete extra hub, some extra studs and lug nuts. Thank God, I didn't loose the wheel. I never felt a thing out of the ordinary the whole trip. Even TPMS would not have helped here.

[AniJet]

lawaco12 wrote:
Be sure there is no oil anti seize on stud wet studs will increase torque up to 4 times applied amount.

Well, somewhat correct. Torque specs are for dry clean studs and nuts. Any lube will cause the effective torque to be up to 25% higher. I have never noticed anyone do this at a shop but the correct (anal) way would be to use contact cleaner on both studs and nuts prior to installation. For critical component assembly always look for a "wet" torque value. On the RV I always lube the threads and reduce the applied torque value by 20%.

To the OP, if the two studs were adjacent to each other, replace all the studs in that hub. If not adjacent you can just replace the broken ones.

[TXiceman]

Oaklevel wrote:
What has changed recently????? I have had cars, trucks & trailers since the 1970s & until my current tire shop have never seen lug nuts torqued. & have never torqued them. Always had put tires on with an impact & never had a lug nut break. I always just used a crossover lug wrench. Is the current wheel stud metal less quality than in the past ???? I have always owned several trailers, trucks & cars. Had rims get bent but no broken wheel studs 🙂

Any knowledgeable tire shop will use a torque wrench to run up the lug nuts to the final setting. You should bring them up to specified torque value in three steps on any aluminum wheel rim.

Ken

[rjsurfer]

I always carry a few spare studs just in case I see one snapped off. Of course a small 4 pound sledge comes along as well to knock them out.
I use a lug nut and a bunch of large washers to pull the new stud in place. Eazzy peezy.

Ron W.

[Wind_Surfer]

Update: I performed the Taco Bell (;)) torque wrench calibration check (hanging weights X's lever arm) and the torque wrench is basically accurate.

I think I will change all the studs when the weather warms up. Priced them out at about $1.60 per stud so not much cost with free labor. Beats having your wheel past you up on the freeway!

[Oaklevel]

What has changed recently????? I have had cars, trucks & trailers since the 1970s & until my current tire shop have never seen lug nuts torqued. & have never torqued them. Always had put tires on with an impact & never had a lug nut break. I always just used a crossover lug wrench. Is the current wheel stud metal less quality than in the past ???? I have always owned several trailers, trucks & cars. Had rims get bent but no broken wheel studs 🙂

[laknox]

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

[lawaco12]

Be sure there is no oil anti seize on stud wet studs will increase torque up to 4 times applied amount.

[rhagfo]

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.

[Dtank]

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

.

[larry_barnhart]

Cummins12V98 wrote:

Me Again 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.

4. What TucsonJim said ^^^! Chris

Yup!

Sounds like good ol Les Schwab at work.

Watch them, they use the impact to run the nuts up then hit the studs once each and the torque wrench does not rotate!

Bottom line they are over torqued before the torque wrench is applied.

Exactly how it was for me.

chevman

[Cummins12V98]

Me Again 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.

4. What TucsonJim said ^^^! Chris

Yup!

Sounds like good ol Les Schwab at work.

Watch them, they use the impact to run the nuts up then hit the studs once each and the torque wrench does not rotate!

Bottom line they are over torqued before the torque wrench is applied.

[time2roll]

If I was breaking studs I would replace them all. New hubs is not a huge cost compared to seeing a wheel pass you by. Or pound them all out and knock in some new ones.

[Wind_Surfer]

Phil, I just used the overlord (google) and most of the trailer sites came up with 120 to 140 ft lbs for a 9/16 stud on aluminum wheel.

SDM - they are 7k Dexter axels/hubs. I would hate to replace the wheels and hubs. That seems like a lot of $$.