The other day I was reading this thinking "These guys are nuts!" So in the past week I have had two wheel studs strip when I removed them. This is since my weekend at Buttonwillow, so I'm thinking that both heat and repeated wheel changing have caused this failure. In the past two weeks I have pulled/mounted my wheels about ten times between Buttonwillow and an 8 hour drift day.
I guess it's only a matter of time before the others strip. I'll be taking the Z in to have ALL the studs replaced. I will have them inspect the hubs while we're at it. ???Do new hubs come with studs, and should I just replace the hubs regardless???

It seems like these full out track events are much harder on cars than autocross or drifting. That being said, I think I'll try to minimize those HPDE's and stick to sub 100 mph action for most of the year.

 

How old is the car, and how many track days have you done with it? I've done 67 track days in my Z since getting it four years ago. In this thread we've only heard of one other car that had a problem similar to mine, so unless you've put a similar amount of stress on yours, replacing the hubs might be a little excessive. .

IMHO, replacing all the lugs is also a bit excessive. I could be wrong, but I don't see how stripped threads can happen while you're driving. My guess is that you're stripping them when you put the wheels on and discovering it when you take them off. Are you using a power tool? I've learned from experience that you've got to be careful and slow getting the nuts started.

So I'd say inspect the hubs, replace the lug bolts that need it, and be careful when you start screwing the lug nuts.

 

I may be over-torquing them with the lug wrench if it's not a heat issue. If they are east to replace, maybe I should try it. I will ask my mechanic how to do it and start using a torque wrench on the lugs. I guess I don't need to worry about the hubs for a while.
Thanks guys.

 

I'd agree with commasense about replacing lugs. After four years of multiple track days, I've replaced only two lugs. Using a torque wrench and starting each wheel nut by hand should be mandatory for either track or street.

 

Oh yeah, if you're not using a torque wrench, that's the problem. The spec is only 80 ft-lbs, and I think a lot of people over-torque their lugs.

BTW, here's a tip about using a torque wrench that a lot of guys apparently don't understand: you're only getting an accurate reading when the nut is still moving. In other words, if the nut is on and tight and you put the wrench on and push and hear a click, but didn't move the nut, it could be overtightened, or possibly even undertightened. You won't know. To get the right torque setting, you must loosen and then re-tighten it until you hear a click while the wrench is still in motion. Then stop! If you keep going after the click, you'll overtighten it. The wrench doesn't prevent that.

At the track, I often see guys put the torque wrench on a tightened nut and push to get a click, and think they've made sure that the nuts are torqued to the right setting. They've probably just overtightened them. RTFM!

 

I don't track as much as Dave or commasense, but I jsut had to replace both wheel bearings on my rear wheels....kinda weird that they just suddenly happened. I thought they would last longer, but abuse doesn't help any.

Dave, thanks for bringing this topic up. Helps the rest of us to be aware of any potential weak areas.

Commasense, I'm here in the deep south for a while longer and it kills me when I see shops just drill on lug nuts with their air gun. Then they torque the wheels and listen for the click. It's funny almost.

-Steve

 

i was replacing studs ALL the time for a bit. the stock studs suck...they are soft. but this was after i had a highspeed spin into the dirt on VIR. On top of that, I was over tightening them. After about the 6th stud broke I finally replaced them all. Its not hard at all, just takes hammer, an extra lug nut (don't wanna burger up the threads on the new one) and a pile of washers. I now carry a pile of extra studs/nuts and a dedicated mess of washers.

Are you re-torquing before each on track session? Cannot tell you how many times I have found several nuts loose before going back out.


i know this is an old thread, but i was revisiting with some of the newer post about maint./hubs ect ect

 

how much is too much torque for the lugs? i usually torque to 85ft-lbs. broke one stud on the front once and replaced the front studs with ARPs.

 

The best place to check is the Owners or shop manuals. Over torquing will definately strip the studs. If I remember correctly the stock 2003 350Z was suppose to be 75 lb/ft. But someone will need to verify that.

 

80 ft/lb.

 

Thank you for the correction

 

Dave and Merlot?

Which Red Line and Royal Purple Diff fluids do you use? I have the 3.9 gear and carbon disc LSD that puts out lots of diff heat as you describe on the track. Used Motul but ready for a test on another product.

 

I have actually switched over to Motul 90PA. I found the redline and royal purple would both get clunky after 1 weekend. The Motul seems to last me at least 3-5 weekends before even starting to protest (at which point, I usually change it out anyways).


I guess I can offer a long term update since I started this threat 2 years ago..
- Stoptechs, never need rebuilding it seems. I took them apart twice to install knockback springs and the inner seals were in perfect shape (excluding fried dust boots).
- Studs - I have never had an issue with the studs that came with my eibach spacers but I did change them this year as preventative maint with the nismo studs.
- Wheel bearings - I will be replacing these at least once per year. I had one of my replacements come loose at end of last season (luckily I noticed it before something really bad happend).
- Nismo LSD will last me a lifetime. I have taken it apart a few times now to adjust settings and found that the internals are also in great shape. I don't expect the plates to ever wear out on me.

 

And don't torgue them HOT! like just right off the track! DO this when it is cold/cool....

You will strech/snap the lug bolts in a heart-beat.

 

Dave and Merlot?

Which Red Line and Royal Purple Diff fluids do you use? I have the 3.9 gear and carbon disc LSD that puts out lots of diff heat as you describe on the track. Used Motul but ready for a test on another product.

 

We switched from Redline to Motul after we overheated our diff. We're driving the car harder than most, so it might not be a fair comparison, but he Motul doesn't give us any problems at all. Of course, we're biased as they're a sponsor, but in all honestly, we couldn't have picked a better fluid supplier.

-Rich

 

Thanks for the Diff Fluid advice gentlemen. Looks like Motul 90A is the favorite