Torque settings on lug nuts?

GSpreeman · GSpreeman's Garage

I am going to pull off the wheels to repaint the centers and adjust or replace the ebrake. I see there are torque settings for tightening down the lug nuts. While this might sound like a retarded question, can't I just tighten them down like regular lug nuts?

pwd72s · 09-08-2002, 07:48 PM

Sure you can...tighten 'em like regular lug nuts! The best way? 96 ft. lbs, in a staggered pattern. Your wheels, your lug nuts, your car, your choice...

304065 · 09-08-2002, 07:53 PM

Also, if a PO has applied anti-seize paste to the bolts, remove it with brake cleaner and a rag. The torque spec (130NM or 96 ft/lb) is a DRY torque setting- if you introduce a lubricant (the paste) you will actually hit a higher torque before the wrench clicks. This is important because your lug nuts are probably anodized aluminum-- don't want to over-torque them.

Dana_Drury · 09-09-2002, 02:55 AM

I believe its 60lb/ft each.

Targa77 · Targa77's Garage

I torque mine at 60

Wil Ferch · 09-09-2002, 05:01 AM

Guys:
Ahhh....ummmm...I think this is wrong.
Torque spec is 94-96 ft/lbs...also lubed...on the threads and more importantly on the round section that "pockets" into the wheel itself.
This has been a hot topic as long as I can remember on Rennlist and also here...and the argument is that lubed is the normal configuration for wheel nuts, and mechanics will *not* get them completely dry to have this be a dry torque spec. I , too, believed ( at first) that this was a dry spec...as normal industry standard is to quote the numbers dry...but it seems lubed in this case. FWIW, it is correct that wrongly using dry spec numbers in a lubed condition will over-torque the fasteners. Typical torque reduction is on the order of 30-40%, if the spec was clearly intended to be dry in the first place.
Test: those who want to "counter-point" this position...please find the specific factory reference that says "dry", either in the factory manual or spec books..I couldn't find it with a lot of searching. But....there is plenty of reference to lube this area with Optimoly, etc etc.

Just another data point....

---Wil Ferch

Jgordon · 09-09-2002, 05:04 AM

My wrench told me 94 lb/ft. I've seen that number repeated in a number of different sources. If there is some confusion, I'd rather have my wheels on tighter than looser.

Reminds me of the far-side cartoon where the guy's in the plane, staring at the "wings stay on/wings fall off" switch.

Jared

Targa77 · Targa77's Garage

no argument there... Looks like I'll have to go home tonight and do some tightening.

Eric Coffey · 11:45 AM

Yep, I believe that 94-96 ft. LB. is the preferred setting, even with a light coat of anti-seize. 60 ft. LB. is too loose. You should/can even bump it up to 105 for the steel lug nuts. Also, when putting the wheels back on the hub, remember to align the valve stem with (closest to) the red stud.

304065 · 09-09-2002, 12:00 PM

Ok, sounds like we are in violent agreement here.

Wil, please don't think I'm trying to be a jerk, but I see the factory manuals a different way than you outlined. When they want you to use a lubricant, like Optimoly or Kuril, they tell you that. So in the absence of a specific instruction from the factory to use a lubricant, I take it that you should not. The fact that the standard practice is to quote the numbers dry supports this view. I know about the debate but I also know that the light aluminum lug nuts aren't as strong as the steel ones and I would be hesitant to over-torque them. I'll check the manuals for my cars, but to break this logjam we may have to call upon Herr Kunz.

My '71 spec book says 13 mkp for the front and rear lugs. This is a German spec, meter-kilopond (was a new one for me).

1 mkp = 7.233 ft/lb
13 mkp = 94.029 ft/lb

but the later spec books say 130NM

1 Nm = .73756 ft/lb
130 Nm = 95.882 ft/lb

Seems like this is the origin of the variance in numbers. My Hazet torque wrench is only accurate to 4% anyway so the variation is moot.

RoninLB · 09-09-2002, 12:25 PM

Trivia...Charles A Stoddard said "As always, the lug nuts securing the wheels should be lightly lubricated on the radiused face and threads".........Ron

GeorgeK · 09-09-2002, 12:43 PM

As per the instructions on my newly purchased (at the dealer) anti theft lugs:
"lightly grease the threads and cones, tighten to 130 NM"
GeorgeK

jwill911 · jwill911's Garage

For over 4 years now I have torqued my original alloy lugs to 94 ft/lbs with light coating of Permatex anti-seize. Two sets of wheels, two sets of lugs. Sometimes more often than a none Porsche owner would think is sane/normal. And I have never experienced a problem, pulled threads or otherwise.

Just my .02

Jim Sims · 09-09-2002, 01:39 PM

Soon to be followed by a Porsche service bulletin no longer recommending the use of thread lubricants (after introducing silver plated wheel stud threads on their latest models) due to lug nut grounding problems (real reason is the dolts were getting it on the brake rotors).

PS: I'd like to see anyone successfully electrically insulate a properly torqued spark plug thread with anti-seize lubricant.

However, I have seen an instance when a person (a graduate of a very prestigious East coast engineering school) managed to get never-seize all over the plug insulators and wires thereby making a real "light show". Dealership service department just laughed and charged him a tidy sum to clean up the mess and redo the job. I wish we knew the real reasons for the service bulletins. Jim

RoninLB · 09-09-2002, 01:47 PM

"It's no exaggeration to say that the undecideds could go one way or another"

.......Ron

GSpreeman · GSpreeman's Garage

Okay, looks like everyone actually torques their lug nuts. Excuse the idiotic question but, can I just go over to the friendly Napa Autoparts place and pick up a torque wrench and do the job?

I really appreciate all the help. Since this is my first Porsche I am treating it with kid gloves so I don't make any costly mistakes.

PS, the fiance caught me cleaning my engine with a toothbrush. Oh, yeah. Just try explaining that one.

pwd72s · 09-09-2002, 08:38 PM

Quote:

Originally posted by GSpreeman
Okay, looks like everyone actually torques their lug nuts. Excuse the idiotic question but, can I just go over to the friendly Napa Autoparts place and pick up a torque wrench and do the job?

I really appreciate all the help. Since this is my first Porsche I am treating it with kid gloves so I don't make any costly mistakes.

PS, the fiance caught me cleaning my engine with a toothbrush. Oh, yeah. Just try explaining that one.

Just go to NAPA and buy a torque wrench??? Oh no, it can't be that simple! You see, a NEW can of worms just opened...click vs. beam torque wrench? Drive size? Measuring range of the wrench selected? And the real biggie...WHAT BRAND OF WRENCH?
After all that? We get into the best type and brand of socket to use...

GSpreeman · GSpreeman's Garage

Well, we're just talking lug nuts here. Any suggestions on the type of torque wrench I should purchase?

Dana_Drury · 09-09-2002, 09:38 PM

Just a decent one that does the job! It all depends, if you
intend to use it for other things then its worth getting a good quality one
that will cover a range of torque settings.

Or, if you just want to tighten your lug nuts then use a decent
30-150 NM Torque Wrench that most good tool stores will sell.

304065 · 09-09-2002, 09:55 PM

Why buy a cheap torque wrench, when you can spend $300 on a Hazet?

Now that's what I'M talkin' about! You dig it the most!

Just don't drop it on your foot. You will have to have it recalibrated. The wrench, not your foot.