Breaking Wheel Studs...

[joefnh]

I have a 03 4.0L 4x4 that I have had an ongoing issue with breaking the wheel studs on the rear wheels. It started after I had one break when the local tire shop was rotating and balancing them about 1 year ago. I had replaced that one wheel stud and after that had others break. At that point I assumed that the studs had been weakened by an over zealous employee with the air gun.

I had at that point decided to replace all of the studs on the rear with factory replacements. When replacing them I was careful never to exceed 90 foot pounds of torque and never used an air gun on them. I had re-torqued them after replacing the studs every 300 miles again never exceeding 90 foot pounds for the next 1000 miles. I have always run factory size 16'" tires

Since that first 'mass replacement' I have had 3 additional occurrences of the studs breaking, each time when one would break I replaced all 5 just to be safe. It has happened on both rear sides. This truck never sees rough driving, it is my DD and only sees simple highway commuter traffic on smooth roads

It should also be noted that at about the same time at the tire shop mishap I had replaced the rear brake rotors during a brake overhaul. I have even had my torque wrench tested for accuracy

Any ideas -- this is not only baffling but quite dangerous.

--Joe

 

[cjones101812]

does the brake rotors have excessive play in them?? can they move/turn on the hubs??

 

[joefnh]

No they basically slide on the studs no more than about 1/16th inch play

 

[joefnh]

Any other ideas?

 

[cjones101812]

not really, as long as the studs are pressed in properly and fully seated, the lugnuts are on properly(tapper towards the wheel) and torqued properly.

 

[210Sooner]

This happened to me once but on an old 79Blazer.
It was my rim that was bad. No matter what side I put that tire on those studs would break. I almost rolled that truck twice cause they kept breaking. I would try moving one of the tires to a different side or running on a spare tire to see if you got the same issue I had.

 

[mrboyle]

Are the studs breaking when you remove the wheel or do they fail all on their own?

 

[joefnh]

What on the wheel could I look for if it were a problem?

The studs break on their own I usually find out when the wheel falls off or if I happen to check it and find 1 or more broken. Lately I have been checking them every 200 -300 miles

 

[dkchrist]

are your brakes getting excessively warm?
Also are the rims fully seating on the hub face?

good luck otherwise

 

[mrboyle]

If the studs are breaking on their own you have a seroius problem! In all honesty I have never heard of this happening and have no real idea where to begin to look.

If it was the wheel causing the problem I can see it coming loose, but not breaking the stud. You may need to take it to a Ford dealer and explain to them what the problem is and see if they have any idea what the problem could be.

 

[joefnh]

Since this started after replacing the rear rotors, is there anything with the rear rotors that I could look for?

Also since when replacing the studs I use an old log nut and some washers to "pull in" the new stud, instead of pressing it in, could this be an issue?

When using that method, I do use a break over style torque wrench to insure that the new stud does not exceed ~95ft/lbs of torque while pulling it in. To help the new stud pull in easier, I pre-heat the hub face around the hole with a propane torch to slightly expand the hole, this allow for less stress on the new stud when pulling it in.

--Joe

 

[mrboyle]

The only way I could see the rear rotors causing the problem is if the casting of the rotor hat was thinner than the stock rotor and it was allowing the lug nuts to bottom out on the stud threads instead of clamping on the wheel face. With the wheel off and the rotor installed, does the sholder of the stud stick out past the face of the rotor more than 1/16"? If it does that may be where your problem is.

 

[joefnh]

The lug nut does not bottom out, and has threads available when tightened.

The wheel is properly mounted and flush and centered on the rotor.

Can anyone think of a problem with using a old lug nut to "pull" the new stud into place.

--Joe