Broken Front Wheel Studs
 

I have had a problem with front wheel studs breaking on my Fairmont. I have found 6 of them broken all the same way. I say found because they never break at the track, I find them on the shop floor after a race, usually 1 to 2 weeks after parking the car. They literally pop off the hub.
First time I suspected I had over torqued the lug nut, replaced the broken stud and torqued all the 1/2 lug nuts to the recommended torque 85-95, I use 85.
Previously I had used an insert on the wheel with a 12 point nut (See picture). After talking with Weld they recommended that I change to a shouldered lug nut which I did. Nothing changed, still breaking studs, sometimes the same one twice. The lug nuts are not bottoming out on the hub when tightened.
The hubs are Aerospace, studs are Moser. Lug nuts are from Weld.
I'm getting frustrated as I don't want this to happen going down the track!

Kelly Lane Stk 4991

Re: Broken Front Wheel Studs
 

From the pictures, it appears you have a very long stud and you may be stretching the stud beyond its yield point. Inferior fasteners will shear as shown in the picture when they are torqued beyond their yield. Therefore, I suggest you go with a shorter stud from either ARP, Mark Williams or Strange Engineering and shorter lug nuts. Also, looking at the cross section of the sheared stud, it appears to show inclusions, typical to inferior material or they may have been improperly heat or solution treated.

Re: Broken Front Wheel Studs
 

Just curious, do the studs thread into the hub OR are they a pressed fit ? I am not a big fan of Aerospace , but I have a hard time placing any blame on them. ARP is a pretty good suggestion. Absolutely nothing wrong with using the sleeve and 12 point nut..... what is the weight of the car ? I would go buy a few LOTTERY tix, you are very fortunate this didn’t happen while going down the track....

Re: Broken Front Wheel Studs
 

Make sure the stud doesn't have a slight chamfer where it transitions to the hex portion. Mine did...a slight chamfer on the hub was needed.

Re: Broken Front Wheel Studs
 

I used to bend/break studs on my dragster just like that, changed to Mark Williams studs and problem was gone.

Re: Broken Front Wheel Studs
 

Those thick Draglites typically use a 3" stud. 2" is too short.

I would definitely go to a Strange, ARP, Moroso maybe, stud. That broken stud looks awful. Just failed.

For what it's worth, right or wrong, I don't pull the front nuts that tight, especially on those 3 piece wheels. Light cars I'll go to 50. Doesn't distort or damage wheels. Never had one come loose.

Re: Broken Front Wheel Studs
 

“Just curious, do the studs thread into the hub OR are they a pressed fit ?”

Screwed in.

Car weighs 3030

Re: Broken Front Wheel Studs
 

I have the same hubs on my car. They are 1/2 inch thread in studs. I have never broken any on my car. I think he has been over torque them. I don’t put that much torque on my 5/8 rear studs.

Re: Broken Front Wheel Studs
 

Those things should actually be fine at 85. Unless they are junk. We pull most OEM street cars to 100 and they aren't 1/2".

When's the last time you checked your torque wrench?

Do you check torque between races? Do they loosen up, like the stud has stretched?

Re: Broken Front Wheel Studs
 

Iam wondering if the inner diameter of the wheel is interfering with the outer diameter of the hub causing a wedge effect.Can you unscrew the broken studs out of the nuts without much effort? If they wont i would think there is some kind of a wedge affect going on..

Re: Broken Front Wheel Studs
 

Also something to look at is what is piloting the wheel , is it the studs or the id of the rim . Might have a runout problem or the rim moving on the hub when coming down from a wheelstand . I run Strange hubs with screw in 1/2" studs and never have had this problem. Lugs torqued to 65 ftlbs.

Re: Broken Front Wheel Studs
 

I torque my lug nuts to 100 ft lbs front and rear and have never had an issue. Those lug nuts look awfully long, are you sure they are not bottoming out on the hub and not tightening correctly on the wheel.

Re: Broken Front Wheel Studs
 

Just for kicks try calibrating your torque wrench or trying one that is known to be accurate.

Re: Broken Front Wheel Studs
 

Breaks the studs on both sides. Car is not capable of wheelstands...yet.
I looked on Welds website for the torque specs.

I’ll check out what pilots the wheel.

Re: Broken Front Wheel Studs
 

I had to remove the stud from the lug nut with vise grips. It wasn’t handy until it was half way out. Never thought about hub interference with the wheel.

My torque wrench is within 4 pounds of my friends new Snap On wrench. I guess I could lower the torque number a bunch.

Re: Broken Front Wheel Studs
 

What’s your BC measurement on the hub and what is it on the wheel.
Early Ford Mustang Fairlane maverick pinto was 4x4.5” and later fairmont models were 4x108mm (around 4x 4.25”).
Make sure you are using the correct BC on wheel and hub.
Studs have fatigue from a register that’s too loose and allowing it to flex.

The pics of your hub stud hole look rough, was it an original Aero Space hub or modified for a different BC?
Not knocking your equipment.....just imo lol.

Good luck

RJ

Re: Broken Front Wheel Studs
 

Plenty of cars out there with Weld wheels and Aerospace brakes, and aren't spitting lug nuts out on the floor. Fit shouldn't be an issue unless parts are made wrong. And unlike axles, front hubs that have the rotors bolted to them don't have a register to center the wheel. Instead they rely on the nuts.

One problem I had with screw in studs in an aluminum hub is the stud backing out of the hub as the nut is torqued. Studs should be torqued into the hub to manufacture's spec (Strange says 65 lb.ft.). I use red lock tight as well. Even doing that they would want to turn. I had to use a socket or tool to hold the head of the stud on the back of the hub while torquing the nut to prevent it.

As has been recommended, I would replace the studs with good USA parts. While talking about length Strange does in fact offer 2 1/2" studs.

Re: Broken Front Wheel Studs
 

Check the hub fit to the wheel center. In the pic of your hub, the inner edge where it transitions to the flat hub looks pretty shiny...like maybe the wheel isn't coming up flat to the flat of the hub.

https://i.imgur.com/xjSaVtWh.jpg?1

Re: Broken Front Wheel Studs
 

If the broken stud wasn't free in the lug nut that tells me that the stud was stretching, and staying stretched, past it's strength limits. Better quality studs should help.

Re: Broken Front Wheel Studs
 

From the picture of the hub and the wheel it looks like it has two different bolt circles. It look like you are using the smallest of the two on the hub. Have you tested the wheel to the larger bolt circle. When we used Aerospace brakes the radius on the back side would not let the shoulder of the bolt seat completely. We had to take a .020” cut to fix and still had to observe radius. Good luck.

Re: Broken Front Wheel Studs
 

Just as a long shot

Do you cross tie downs when towing. Am pretty convinced those that tie down straight front and back not crossed allow a lot of side to side movement while towing which causes most of the wheel cracking.
It's a stretch but this would also put some stress on the lug studs.

Re: Broken Front Wheel Studs
 

Were the wheel studs made in China?

Re: Broken Front Wheel Studs
 

I checked the hub size compared to the wheel size, there is a difference however the wheel has a small step on the inside to accommodate the hub (see picture). I removed the hub and bolted it to the wheel it fits just fine, no binding or tight spots.
Original un-modified Aerospace hub. I purchased them new.

Studs are Moser's not sure where they are made. I have ordered a set of Mark Williams which are manufactured by ARP. I always lock tight the studs on the hub as they are a true screw in stud without a head.

I do cross my tie downs on the rear but not the front, didn't consider that might be too much side load.

I made sure the small bolt pattern on the wheels matched the small bolt pattern on the hub. Fit is good putting the wheel on the hub.

The first 18 months I raced the car there were no issues, then boom.

Lot's of good ideas from you guys, I'll keep looking.
Thanks

Re: Broken Front Wheel Studs
 

Mine have a regular head and come with washers with a chamfer on the ID . They are torqued and I use locktite . The picture of the Moser studs you have don't have a head. so do they come with a jam nut ?

Re: Broken Front Wheel Studs
 

Nope, but the MW’s I ordered have a head.

Re: Broken Front Wheel Studs
 

I think you got your solution right there,I have sheared a Moser stud for no real reason, looked like they had cut threads instead of rolled,I decided to go away from Moser totally at that point and got axles,spool,bolts and misc. stuff from M/W,just put the stuff side by side and you will never look back!

Re: Broken Front Wheel Studs
 

I agree the Moser studs look like low grade stuff. I have Moser axles and spool also. So far so good on them. My car is a low hp U/S car so I thought the stuff would hold up.

Re: Broken Front Wheel Studs
 

A headless stud is dependent on the threaded fit between stud and hub for alignment. Lacking a head, the stud is going to pivot in the hub thread and be loaded/twisted along it's length as the wheel nut is torqued. Not hard to imagine what happens then. -Al

Re: Broken Front Wheel Studs
 

I have had this happen, a spacer between the wheel and the hub caused the studs to brake. I'm not sure from the pictures but, is there some kind of spacer on your hubs?

Re: Broken Front Wheel Studs
 

Granted I don't pay attention to what every company offers outside of my preferred sources, but I have never seen a headless stud offered for this application outside of the 5/8 drive studs using jamnuts of rear axles. Nor would I consider using them.

I don't want to bash anyone who supports racing, but that's a head scratcher.

Re: Broken Front Wheel Studs
 

I bought some Moser studs for my rear axels, and i was not impressed with the quality.

Re: Broken Front Wheel Studs
 

The center bore on the wheel is something that was a problem when going to aftermarket brakes. Depending on the wheel brand, either the wheel had to be machined to accept the hub, or you had to run a spacer under the rotor hat. Even though the wheel would appear to sit flush on the hub, it would be off and start to bend the stud if you forced it to tighten up. This was something more specific to the 4 lug wheels compared to any of the 5 lug. So then even at a torque spec of 50lbs, it wouldnt torque correctly but it would tighten up. Would cause a pretty good vibration in the front end rolling along that you could chase for a bit.

Re: Broken Front Wheel Studs
 

Proper torque is affected strongly by cleanliness of threads, coating on the threads, type of lube,