Lug nut thread engagement

[hunt2elk]

What is your opinion on minimum thread engagement for lug nuts? I am switching from Crager SS unilug wheels to the direct drill model which takes a 60* conical nut. Standard length wheel studs give me about 3/4" of threads in the nut. Should be fine, correct?

 

[kiwigtx]

I am no expert at this, but the lugs on my A100 for the new wheels stop short about 1/4" from bottoming out inside the nut (if that makes sense. In other words, I have almost as much lug thread inside the nut as is possible.

 

[Fran Blacker]

1/2" stud 1/2" of thread engagement minimum .What I've been told.

 

[steve340]

Rule of thumb for a fastener is 1.5 times the diameter will cope with maximum torque.
So 3/4" of thread in the nut should be fine. You would probably only torque them up to 65 ft/lbs

 

[6872n73]

Generally speaking 1 1/2 X bolt diameter is very good thread engagement and 1 X bold diameter in minimum.
So if your studs are 1/2" * 1.5 = 3/4" engagement....that'll do donkey, that'll do.

 

[67MPRFAN]

I just swapped wheels and realized I'm going to need longer studs

 

[MoparHonda]

Thank you, I also had the same question.

 

[casey henson]

I just swapped wheels and realized I'm going to need longer studs

View attachment 968164

looks familiar...I am not finding a 1/2" stud that I like with a longer reach.

 

[hunt2elk]

looks familiar...I am not finding a 1/2" stud that I like with a longer reach.

View attachment 978527

Here is the response I got from Cass aka Dr. Diff. I ordered and have the longer studs, but haven't got them installed yet.

"I would try Dorman # 610-290, or Moroso for the front:
https://www.summitracing.com/parts/rnb-610-290
https://www.summitracing.com/parts/mor-46180

Mr Gasket rear studs are the closest to what you are looking for. No other brand of long stud has the correct knurl size See below:
https://www.summitracing.com/parts/mrg-4311/overview/

If you install the extra long studs, you must cut the end of the fastener, or run open ended lug nuts.

Cass"

 

[HALIFAXHOPS]

Rule of thumb for a fastener is 1.5 times the diameter will cope with maximum torque.
So 3/4" of thread in the nut should be fine. You would probably only torque them up to 65 ft/lbs

That's what we used in the USAF, was the standard from the technical manual on the fasteners.

 

[casey henson]

Here is the response I got from Cass aka Dr. Diff. I ordered and have the longer studs, but haven't got them installed yet.

"I would try Dorman # 610-290, or Moroso for the front:
https://www.summitracing.com/parts/rnb-610-290
https://www.summitracing.com/parts/mor-46180

Mr Gasket rear studs are the closest to what you are looking for. No other brand of long stud has the correct knurl size See below:
https://www.summitracing.com/parts/mrg-4311/overview/

If you install the extra long studs, you must cut the end of the fastener, or run open ended lug nuts.

Cass"

I have a 610-290. it is good but not much longer. I really need more because I might use a small spacer.
I do also have some 46180's coming but I dont really care for the shorter knurled area.
I am actually considering going to 14mm studs. I have found one with a knurl that I like.

 

[alfaitalia]

I was always told that the absolute minimum engagement is the diameter of the thread....as said above.

 

[Durandal25]

I am no expert at this, but the lugs on my A100 for the new wheels stop short about 1/4" from bottoming out inside the nut (if that makes sense. In other words, I have almost as much lug thread inside the nut as is possible.

View attachment 968134

View attachment 968135

....if I never said it before, your A100 is a thing of awesomeness sir.

 

[33 IMP]

I am disappointed by the new fascination with conical seats on mag wheels. There has to be a reason, either cheaper or easier for the manufacturers, but it just causes stud problems on our old cars.
Assume a stud with 3/4" of working thread. If your wheel center is a 1/2" thick, you now have a quarter inch of thread left. With the old style mag lugs, with the shoulder inside the wheel center, you had all 3/4 inch threads to use.
Now, with these new wheels you almost always need new long studs, and you always do if you need to use a spacer. The trouble is FINDING new longer studs that can work.
I have a couple sets of the conical seat wheels, and in both cases, the car already had 3" studs, but I prefer the old style mags lugs.

 

[steve340]

The conical wheel nuts are used because they locate the wheel in a more "true" fashion.
Also because of the tapered seat they are less likely to come undone.
Aluminium road type wheels need to be around twice as thick as steel so that does make a problem on an older vehicle designed for steel rims.