6SpeedOnline - Porsche Forum and Luxury Car Resource

6SpeedOnline - Porsche Forum and Luxury Car Resource (https://www.6speedonline.com/forums/)
-   996 Turbo / GT2 (https://www.6speedonline.com/forums/996-turbo-gt2-2/)
-   -   Snapping Lug's? any help? (https://www.6speedonline.com/forums/996-turbo-gt2/339793-snapping-lugs-any-help.html)

'02996ttx50 Jun 18, 2014 05:29 AM

Snapping Lug's? any help?
 
i'm currently running forgestar wheels in 9 x 12 fitment. i continue to snap wheel lugs at an alarming rate.

it began when i first fit them and used the shiny lugs of a presumably asian origin :rolleyes: and although i have used a number of different kinds of bolts, they still are conical 14mm/1.5 in bolts. pretty standard fare. since converting to rwd i am snapping them in half, and just removed wheels to get bumpers off etc and found three more bolts had sheared! this after changing out for new rear rubber a month ago. all bolts torqued to spec, at the time.

i realize i'm putting some power down with the combination of my wavetrac tbd/lsd and roughly 475+rwhp and a lot of cambered turn powered throttling out of apexes?! but this is insane and potentially quite dangerous. so what is next?! do i drop the few hun on the tikore titanium? and will that cure this? i'm wondering now if it's the wheels themselves? they are not "hubcentric", but that added spacer ring shouldn't have an impact on this issue. the lugs do seem to have some discoloration ( water rust?? ) but i dry the wheels as best i can if/when i ever wash the car lol

torquing to 90 - 96 ft lbs. any info, comments/advice or whatever is greatly appreciated. scary proposition this.... :eek:

rmc1148 Jun 18, 2014 06:35 AM

When you say sheered are they actually snapped completely off. I would think something is not seating correctly. I would use only OEM quality or better and never anything cheap. Go for the strongest you can get.

Engine Guy Jun 18, 2014 06:36 AM

You could have several issues working against you.


A wheels biggest holding power is due to the friction created from the wheel surface mating with the hub flange as a result of the torque from the lug bolts jamming the two together. When a wheel fits together properly those two surfaces hold together so well that the lug bolts do not endure much more then a stretching force.


Well now factor in a wheel that does not fit quite propperly for its application and what sounds like some lug bolts that are in question and you have yourself a very expensive and potentially dangerous recipe for disaster.

If they are a really cheap lug bolts replace them immediately without question!!!


But first make sure you know what the proper taper is as that could be the issue right now, is the taper of these said bolts the right taper for these wheels? You will notice that the bolt head has a tapered neck, if that taper does not match the taper of the wheel you lose out on another area where good surface contact creates friction and strength.

Loose one or more of these contact areas and then the lug bolts likely are having to take lateral, sheer or bending loads too.

So your primary task is to make sure the taper on your lug bolts matches your wheels. The the fit of your wheels to the hub flanges is secondary but still important, especially if they are too tight for each other. Namely the flat part of the wheel flange should sit flat on the hub flange, if the hub centering ring does not allow the wheel to mount properly you are done! Also the quality of your lug bolts is important but not the greatest initial concern, properfitment is #1.


Get those details right and a properly mounted wheel would take many many years of service with way more Hp then your car puts out!


It is not just as simple as using a strong part, the strong parts must fit or match each other. A strong bolt that does not have the right taper will fail.


'02996ttx50 Jun 18, 2014 06:44 AM

kyle thx. will read and re-read all this again! agreed the whp *shouldn't" be "the" issue?! but these wheels are used by guys tracking ll the time. i can't be the only person this has happened to.. and there are MANY anecdotal reports of the supplied forgestar bolts failing like this. but this seems to be ANY 14mm 1.5 i've tried.

rmc.. i think the shank size is different from the oem. there's a reason the concial seat 17mm oem's can't be used. need to sort out why!

add: replaced 10 last night. will run them and check for torque asap after a good cpl days

rmc1148 Jun 18, 2014 06:52 AM

What brand wheel are you using?

'02996ttx50 Jun 18, 2014 06:54 AM

forgestar.. as per above ;)

rmc1148 Jun 18, 2014 07:06 AM

Sorry missed that. If you can talk to rep from company or other same wheel user they may shine some light on issue.

'02996ttx50 Jun 18, 2014 07:17 AM

well a quick search turned up a 2 yr old thread in which i was *****ing about the same issue and a rep from a vendor said (paraphrasing) that the propensity for lug failure at least of forgestars supplied bolts, has been known to happen to folks on "the track". so, again, i'm not the only one this has or happens to surely. i should probably ditch em.

rmc1148 Jun 18, 2014 07:22 AM

Agreed if your having this problem as well rep acknowledging its time for a new set up before something bad happens. Better new wheels/money spent then hospital or worse.

Engine Guy Jun 18, 2014 07:34 AM


Originally Posted by rmc1148 (Post 4137424)
Better new wheels/money spent then hospital or worse.

Even if you do not hurt yourself or even someone else the thousands of dollars usually spent fixing a car when a wheel comes off a car is enough incentive.

'02996ttx50 Jun 18, 2014 10:04 AM


Originally Posted by Engine Guy (Post 4137432)
Even if you do not hurt yourself or even someone else the thousands of dollars usually spent fixing a car when a wheel comes off a car is enough incentive.

Well have my eye on a possible set of new wheels. but either way I'll obviously be checking these bolts weekly.

996TWINS Jun 18, 2014 10:28 AM


Originally Posted by '02996ttx50 (Post 4137537)
Well have my eye on a possible set of new wheels. but either way I'll obviously be checking these bolts weekly.

I had the same issue with the lug bolts supplied by Forgestar. Surprised they have not dumped them all, and supplied a better quality lug bolt by now.

Buy a better set of lug bolts and no worries. Check out Pure Motorsport.

'02996ttx50 Jun 18, 2014 10:38 AM


Originally Posted by 996TWINS (Post 4137556)
Buy a better set of lug bolts and no worries. Check out Pure Motorsport.

i only used the forgestar supplied bolts when i got the wheels and the issue has persisted regardless of mfg'r. there's three separate events involving snapped lugs. but these have all been generic bolts. there are not many choices it seems in a 14mm conical 1.5! i will check out Pure MS. thx for the tip.. and wondering if anyone knows the benefit of the insanely expensive tikores.. "

TeCKis300 Jun 18, 2014 11:34 AM

I would re-examine the bolts your using first before suspecting the wheels. Also, IMO it's not good enough that you regularly inspect as you can't detect whether they're close to failure until they actually fail.

Can you name the brands/sources of the bolts you've tried. I think it's important to share that so others don't experience these same issues.

Have you tried McGard bolts? These have a 17mm drive heads (smaller than the 19mm stock bolts) so they will fit any wheel. More importantly, these have 2-piece washer design similar to stock -

'02996ttx50 Jun 18, 2014 11:48 AM


Originally Posted by TeCKis300 (Post 4137624)
I would re-examine the bolts your using first before suspecting the wheels. Also, IMO it's not good enough that you regularly inspect as you can't detect whether they're close to failure until they actually fail.

Can you name the brands/sources of the bolts you've tried. I think it's important to share that so others don't experience these same issues.

Have you tried McGard bolts? These have a 17mm drive heads (smaller than the 19mm stock bolts) so they will fit any wheel. More importantly, these have 2-piece washer design similar to stock - Amazon.com: McGard 67200 Chrome M14 x 1.5 Thread Size Cone Seat Lug Bolt Wheel Installation Kit for 5 Lug Vehicles: Automotive

but that's the thing. the bolts are generic! it isn't often ( cheaper/generic ) lugs are branded. which is why i am now searching for reputable "branded" ones to replace.. and of course i'll be inspecting them fastidiously moving forward. my wheels come off fairly regularly for one reason or another so unless i know a bolt snaps and something major is felt?? i'll still "know" it soon enough.

the ones i got at 7pm last night were off the shelf at pep boys and i felt lucky to even find them or my car would be on jackstands now! but i have zero confidence in them as replacements although "new" since they are exactly what tire shops have been using. there isn't really a brand that anyone would recognize. they're cheap shyte no doubt.

i'll be extensively searching out the recommendations, and appreciate the input. the link to those says they are 14mm but 17mm hex? need to see if those are the correct fit. i thought 14mm was the hex size. oh,.. 17mm heads. got it.. thanks!

add: says theyre not a "fit" for oem but neither is the wheel! it's made to fit our cars only with the hubcentric "ring" so i need to determine if the ones in the link will in fact fit. all i know is a need a 14mm 1.5. so my next stop is a wheel shop.. no chance of getting forgestars help lol


All times are GMT -6. The time now is 03:53 PM.


© 2026 MH Sub I, LLC dba Internet Brands