# Restoring lug stud threads



## mark sr (Jun 13, 2017)

I've chased existing threads many times although I don't ever recall doing so on wheel lugs. A lot depends on how bad the existing threads are.


----------



## Nealtw (Jun 22, 2017)

That is not a good idea. Now you have changed the specks of the bolt and you don't know how they will deal with the torque required. They don't sell undersized nuts for re tapped threads.


----------



## Bigplanz (Apr 10, 2009)

Nealtw said:


> That is not a good idea. Now you have changed the specks of the bolt and you don't know how they will deal with the torque required. They don't sell undersized nuts for re tapped threads.


The stud is 14mm, 2.0 thread pitch. The die is the same. Cleaning and regrooving the damaged portion but not resizing the stud. Lugnuts went back on securely. Replacing the studs is the right method, but pulling the diff cover and pulling the axle is a drag.


----------



## Nealtw (Jun 22, 2017)

Bigplanz said:


> The stud is 14mm, 2.0 thread pitch. The die is the same. Cleaning and regrooving the damaged portion but not resizing the stud. Lugnuts went back on securely. Replacing the studs is the right method, but pulling the diff cover and pulling the axle is a drag.



When you hear a strange knocking noise while you are driving, suspect a wheel first, you have about a mile to figure it out.


----------



## Bigplanz (Apr 10, 2009)

Of course, it could be that, or the lower trailing arm, which I discovered is falling apart on that side. Bonus footage!


----------



## de-nagorg (Feb 23, 2014)

Please , just change out those studs.

You are valued here, as well as by your family. 

I am speaking here as an experienced driver that has lost a wheel at highway speeds, You don't want that BOAT that you drive set loose on the road, when it's wheel comes off.

Should I say, " There will be blood", maybe not yours, maybe yours, but the point is that and change at all in the mounting of wheels is a definite loss of the wheel, sometime later. 

I would not like to hear of someone there hurt or worse, because someone was too busy to do it right the first time. 

Please do get those changed ASAP.

PLEASE


ED


----------



## Bigplanz (Apr 10, 2009)

de-nagorg said:


> Please , just change out those studs.
> 
> You are valued here, as well as by your family.
> 
> ...


Ok. I will add it to my list:

Rear brakes, pads and rotors
Get e-brake working.
Rear trailing arms, both sides
Track bar replaced
Change transfer case fluid
Replace differential oil and new cover. 
Rear lug studs, probably both sides.
New serpentine belt, tensioner and idler pulley
Probably the passenger side balll joint and UCA. I did the driver's side last fall.

My neighbors love it, since I only have the street in front of the house to work on stuff. I have a friend who owns a bar and he told me I could use his back parking lot. Not much work would get done though. :biggrin2:


----------



## Dave Sal (Dec 20, 2012)

de-nagorg said:


> I am speaking here as an experienced driver that has lost a wheel at highway speeds, You don't want that BOAT that you drive set loose on the road, when it's wheel comes off.



When I was about 16, I went on a little shopping trip in a suburb of Chicago with my buddy and his mom. My buddy was driving his 1970 Chevy Chevelle SS396 and we had to go about 10 miles south on I-94 to get to the store. On the way back, the right rear wheel goes flying off and we end up spinning around like a top. I was in the back seat and saw my life flash before my eyes. :biggrin2:
We were lucky that a tractor trailer didn't smash into us. Ended up on the shoulder where we managed to get the spare tire mounted and continued on our way. Turns out my buddies younger brother had used the car the night before, got a flat and changed it but never properly torqued the lug nuts. Not fun.


----------



## mark sr (Jun 13, 2017)

While I won't disagree that replacing the lugs is best and while I've not seen the lugs prior to chasing the threads, I'm not convinced they are unsafe. I would regularly check the lugs with a torque wrench until I became convinced either way.


Back in the 70s I had a wheel off and was putting it back on when my girlfriend stopped by. After she left I let down the jack and put on the hubcap ..... with the lugs only finger tight. I don't remember how many miles but I figured it out the next time I drove it. Never felt I was in danger although if I had continued to drive it that way I'm sure I would have been. It did wallow out the lug holes on the rim.


----------



## Bigplanz (Apr 10, 2009)

mark sr said:


> While I won't disagree that replacing the lugs is best and while I've not seen the lugs prior to chasing the threads, I'm not convinced they are unsafe. I would regularly check the lugs with a torque wrench until I became convinced either way.
> 
> 
> Back in the 70s I had a wheel off and was putting it back on when my girlfriend stopped by. After she left I let down the jack and put on the hubcap ..... with the lugs only finger tight. I don't remember how many miles but I figured it out the next time I drove it. Never felt I was in danger although if I had continued to drive it that way I'm sure I would have been. It did wallow out the lug holes on the rim.


I keep a torque wrenchjn the SUV in case I need to change a tire. I torqued them to 150, and everything was tight. Had a slight wobble feeling when I drove it, but then realized I had forgotten to turn the air suspension back on. Drives fine now.


----------



## mark sr (Jun 13, 2017)

You should keep checking them periodically to make sure they stay tight.


----------



## Nealtw (Jun 22, 2017)

High rated nuts and bolts are hard, the threads will stretch safely to the limit of the torque required, the threads should be strong enough, so the bolt breaks before the threads are distorted. So if the bolt has been over torqued and the threads are distorted, the bolt is in question already as it was not hard enough.
What ever caused the threads to be distorted they should be hard enough that you can't just push then back in place. So you are cutting metal away. 

Most books that talk about chasing bolt threads also mention to over torque to make up for the missing metal. So over torquing because the bolt could not take the book stated torque and now you have less steel and you are going to fix it with over torquing. 

JMO, there is no fixing a lug bolt. If the lugs were never over torqued then the bolt isn't as hard as advertised and was over torqued when torqued by the book.


----------



## Bigplanz (Apr 10, 2009)

I damaged the studs a couple of years ago. I had a flat and put the spare on. I read the torque spec as 100 ft pounds, but that is for the 12mm stud. The 14mm stud is 150. Was driving on a city side street, maybe going 10 mph and the wheel came off. Fun times!

The wheel was in the wheel well, but it dropped the SUV. I jacked it up, put it back on and got a new tire right of way. Studs were marred, but the nuts would still go on them. I noticed a die online the same size and pitch as the stud, so I decided to c,ean them up. I am doing the rear brakes now that the weather is warm so I replace the studs then.


----------



## Nealtw (Jun 22, 2017)

Bigplanz said:


> I damaged the studs a couple of years ago. I had a flat and put the spare on. I read the torque spec as 100 ft pounds, but that is for the 12mm stud. The 14mm stud is 150. Was driving on a city side street, maybe going 10 mph and the wheel came off. Fun times!
> 
> The wheel was in the wheel well, but it dropped the SUV. I jacked it up, put it back on and got a new tire right of way. Studs were marred, but the nuts would still go on them. I noticed a die online the same size and pitch as the stud, so I decided to c,ean them up. I am doing the rear brakes now that the weather is warm so I replace the studs then.


Good plan. I lost a front tire just as i was stopping at a red light, I had to jump out and stop traffic while this wheel was doing the 20 ft bounce in every direction.


----------



## mark sr (Jun 13, 2017)

How do y'all not feel a loose wheel before it's bad enough to fall off?


----------



## Nealtw (Jun 22, 2017)

mark sr said:


> How do y'all not feel a loose wheel before it's bad enough to fall off?


 Mine could not be felt in the steering and it had just started with thumping and I thought it was a U joint, I was planning to pull over after the light.


----------



## HenryMac (Sep 12, 2018)

The wheels studs need replaced.

Not only has the root diameter been compromised, but it's obvious somebody at some point drove the car with the lug nuts loose.

Also, there's a big difference in strength between rolled threads and cut threads. 

"rolled threads have documented fatigue life much better than cut threads"

https://www.portlandbolt.com/technical/faqs/rolled-vs-cut-threads-bolts/

Have you tried pulling the brake caliper and then sliding off the rotor? It might be a lot easier than you think. I find it hard to believe it would be designed such that the rear axle needs to be pulled to replace wheel studs.

And the trailing arm video would suggest that this vehicle should not be driven until those are replaced too... especially since you've posted video's acknowledging the poor condition on a website.


----------



## Nealtw (Jun 22, 2017)

The axle does have to be slid out some to work on them.


----------



## HenryMac (Sep 12, 2018)

Nealtw said:


> The axle does have to be slid out some to work on them.


I stand corrected. My apologies to the OP.

Note to self: Another reason not to buy a Ford or a Lincoln.

It would have been easy to design a recess in one spot to remove the studs, but it would have cost them 20 cents per vehicle.


----------



## Nealtw (Jun 22, 2017)

HenryMac said:


> I stand corrected. My apologies to the OP.
> 
> Note to self: Another reason not to buy a Ford or a Lincoln.
> 
> It would have been easy to design a recess in one spot to remove the studs, but it would have cost them 20 cents per vehicle.


I am sure they could have modified the break shoe to allow the stud to be replaced


----------



## HenryMac (Sep 12, 2018)

Nealtw said:


> I am sure they could have modified the break shoe to allow the stud to be replaced


Agreed. Hard to say without seeing it but I'm wondering if the OP could:

Cut the bad stud off with a grinding wheel, 
knock the stud hub through the back of the axle face plate,
use that axle face plate stud hole to drill through the backing plate,
re-drill the backing plate to a diameter big enough for the new stud to pass through,
install the new stud,
insert a plug into the backing plate hole.

FORD

Fix
Or
Repair
Daily


----------



## Nealtw (Jun 22, 2017)

HenryMac said:


> Agreed. Hard to say without seeing it but I'm wondering if the OP could:
> 
> Cut the bad stud off with a grinding wheel,
> knock the stud hub through the back of the axle face plate,
> ...


 I think the problem is the break shoe for the parking brake. 

found on road dead.


----------



## HenryMac (Sep 12, 2018)

Nealtw said:


> I think the problem is the break shoe for the parking brake.
> 
> found on road dead.


Which could have been placed on the yoke of the rear differential.


----------



## Bigplanz (Apr 10, 2009)

HenryMac said:


> Agreed. Hard to say without seeing it but I'm wondering if the OP could:
> 
> Cut the bad stud off with a grinding wheel,
> knock the stud hub through the back of the axle face plate,
> ...


I actually did think about all of the above. Nah, why trash your car like that? Sort of like people cutting access holes for the fuel pump so they don't have to drop the tank. Really??

It is a thoughtless design, just as it is thoughtless not to leave an access hole for a fuel pump. I am not going to disfigure my car over it though.


----------



## huesmann (Aug 18, 2011)

That axle end looks just like the one for my Mustang—I assume your vehicle has a Ford 8.8" rear end? I was able to change the studs on my axles without opening the diff case to release the axle C clips by ever so slightly grinding off the flange on the studs, creating a flat that would let the stud slip by whatever was blocking it.

What year F-150? Look to be a number of videos on YT that deal with rear lug replacement.


----------



## Bigplanz (Apr 10, 2009)

My 2000 Navigator has the 9.75 differential (based on the shape of the cover). I bought a new lower control arm, so when I replace it, I will pull the brake rotor. There might be a way to get the studs out if I remove the parking brake shoes. Doubt it though.


----------

