Pontiac G8 Forum banner
1 - 15 of 15 Posts

·
Registered
Joined
·
69 Posts
Discussion Starter · #1 ·
My new wheels came in last week and I finally had a chance to test fit them (without tires) the other day to ensure that they were made to spec (centerbore, bolt pattern, etc.). The fit is perfect, except that I'm a bit worried about the amount of engagement (or lack thereof) of the lug nuts. Because the wheels are higher offset than stock, I'm only getting about 6.5 full turns of the nuts before snugging down on the wheel. I believe I was getting about 9.5 full turns on the stock GXP 19s. Does anyone have any insight on this subject? Do you think 6.5 turns is acceptable or do I need longer studs? Am I flirting with death and destruction here? I know that if I need longer studs it's going to be an expensive repair bill (with the requirement that all of the wheel bearings be replaced at the same time). At the same time, if it's a health and safety issue, I suppose I will bite the bullet.

The tire rack's website suggests that 7.5 turns is the "minimum number of turns of hardware engagement" for our sized studs (14 x 1.5 mm). The wheel manufacturer told me that 6.5 turns should be fine, but that I should check them shortly after initial install to see if they're getting at all loose, which would indicate that there isn't enough engagement.

Thanks for the input.
 

·
Registered
Joined
·
2,145 Posts
I think at least 6 full turns is acceptable. That's the rule of thumb in my business, 6 full turns. I'd double check though.
 

·
Premium Member
Joined
·
1,647 Posts
3 full threads is the minimum in my line of work, but then again we're talking about #0-#10 screws LOL.

In all seriousness, though: I don't know what kind of steel the nuts and studs are made out of, but assuming they are similar to each other, you could use the old rule of thumb that the length of engagement of the threads should be 1X (minimum) the diameter of the male threaded part (the stud). The key is that you want the shear strength of the threads to be at least as strong as the tensile strength of the stud itself.
 

·
Registered
Joined
·
2,145 Posts
Turbo, you so smart. Good info.
 

·
Premium Member
Joined
·
1,647 Posts
I try ^_^.

Most of my customers demand 1.5X engagement on my products, but aerospace always has to be special LOL.
 

·
Registered
Joined
·
1,787 Posts
Turbo301s advice is sound. A visual check is that the stud thread makes it just past the nut threads.

(#10s really? Some our bigger stuff is like a foot in diameter and 6 ft long)
 

·
Premium Member
Joined
·
1,647 Posts
Turbo301s advice is sound. A visual check is that the stud thread makes it just past the nut threads.

(#10s really? Some our bigger stuff is like a foot in diameter and 6 ft long)

Wooeee, that is quite the screw! Whatcha making with those puppies, oil rigs or somethin'?

Yup, the biggest screw any of my products use is a #10. Now, some are A286, but that's my only consolation to bigness :D.

I had considered the advice about the stud showing through the nut, but I wondered if the OP might be using blind nuts (like "tuner lugs"). Also, OP, the "starter threads" used on many automotive lugs shouldn't be considered in the thread count.
 

·
Registered
Joined
·
69 Posts
Discussion Starter · #8 ·
Yes, unfortunately I'm using blind nuts. I have the OE nuts, which are open, and I suppose I could cinch those down and see how much (if any) comes through. I won't, however, be able to tighten them because they aren't the proper conical shaped nuts for the wheels.

In my count of the # of turns, I basically started the nut on the stud to the point where I couldn't simply pull it straight off the wheel and then started counting each 360 degree turn from there.
 

·
Registered
Joined
·
848 Posts
For full engagement equal to diameter is about 9 turns.. 14mm stud at 1.5mm pitch is 9.3 turns.

There are extended thread nuts available from Gorilla.. You need to get your wheel's stud holes enlarged to 5/8inch but then these nuts extend into the wheel stud holes and allow greater thread engagement.

 

·
Premium Member
Joined
·
1,647 Posts
Good info Jon, I couldn't recall the size or pitch.

OP, I don't know if I'd risk your current setup. That's only 67% of diameter.
 

·
Registered
Joined
·
69 Posts
Discussion Starter · #11 ·
So what are my options if I go the route of longer studs? Does anyone know who sells them or where to get them from?
 

·
Registered
Joined
·
1,793 Posts
I would do longer lugs personally. Its a call, and it would probably be alright... but I hate to chance it...

I would do DORMAN 610-428... they are a bit longer and work great with most longer duplex length lug nuts..

There are no ARP studs that will fit our cars that are useable in your case... unless they just came out with them in the last week... :)..

You could go to a GM dealership and get lugs made for the full size GM pickups made in the last couple years... they are slightly longer also... there are threads on lugs that explain all this...

Also you dont need to remove the brg or anything to replace the lugs.... the fronts are easy and very painless.... the rears, as explained in a couple other threads, (if you dont want to remove a bunch of stuff and be costly) you can drill thru the back of the dust shield in the rears and rotate to a spot where is virtually clears by the hub and then might have to grind a tiny spot on the hub to get the lugs out and in.... but it takes it from a 5 hour job on the rear to only 40 minutes max per side...

others have posted pics also but if you need pics I can send what I did.... may take me a bit to send but I will post if you want...

good luck!!!
 

·
Registered
Joined
·
1,787 Posts
I agree, a little short for comfort. All you need is a thread on a stud or nut to be sloppily cut and it will be on the ragged edge of stripping out. With the affordable stud changeout method provided, it's a no brainer. Be safe.

(Big or little, same equations apply for threaded fasteners. The quality of the materials and forming make the difference. 4340 for dry and X-750 for wet locations are popular choices. A286, nice stuff)
 

·
Registered
Joined
·
69 Posts
Discussion Starter · #15 ·
GR8Lover, thanks for the info. I have seen that other thread that discusses taking the lugs out from the back of the dust shield. If you have pictures, that would be most excellent.

I'm definitely going the route of getting longer studs. I don't want to have to think about it in the back of my head whenever I'm driving the car hard. That's the last thing I need.
 
1 - 15 of 15 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top